# interfacemirror

Brent@GMATPrepNow posted a reply to If xy is not equal to zero, what is the ratio of x to y? in the Data Sufficiency forum
“NOTE: We can write the ratio x:y as a fraction x/y Target question: What is the value of x/y ? Statement 1: 3x = 4y Divide both sides by y to get: 3x/y = 4 Divide both sides by 3 to get: x/y = 4/3 So, the answer to the target question is x/y = 4/3 Since we can answer the target question ...”
Today
Brent@GMATPrepNow posted a reply to At the Trenchard Oaks apartment complex, a two-bedroom in the Problem Solving forum
“A fast and easy approach is to assign a "nice" value to the monthly rent of a ONE-bedroom apartment. Let''s say the rent on a ONE-bedroom apartment is $100 per month A two-bedroom apartment costs 50% more to rent than a one-bedroom apartment 50% of$100 = $50 So, the rent on a ...” Yesterday Rich.C@EMPOWERgmat.com posted a reply to In a certain game, a large bag is filled with blue, green, in the Problem Solving forum “Hi All, This question involves a bit of logical thinking and factoring skills. You have to take notes and stay organized though, if you want to answer this question correctly. We''re told: Blue chips = 1 point each Green chips = 5 points each Purple chips = X points each (more than ...” Yesterday Brent@GMATPrepNow posted a reply to If line k in the xy-coordinate plane has the equation Ax + B in the Data Sufficiency forum “ Given: Line k has the equation Ax + By = C Target question: What is the slope of line k ? This is a good candidate for rephrasing the target question. Let''s take the given equation Ax + By = C and rewrite it in slope y-intercept form, y = mx + b, where m = slope and b = y-intercept ...” Yesterday Brent@GMATPrepNow posted a reply to What is the ratio of x:y:z? in the Data Sufficiency forum “Target question: What is the ratio of x:y:z? Statement 1: xy = 14 In information about z Statement 1 is NOT SUFFICIENT Statement 2: yz = 21 In information about x Statement 2 is NOT SUFFICIENT Statements 1 and 2 combined There are several values of x, y and z that satisfy BOTH ...” Yesterday Brent@GMATPrepNow posted a reply to If xy : yz : zx = 1:2:3, then what is x : y : z ? in the Problem Solving forum “Let''s focus on pairs of values If xy : yz : zx = 1:2:3, then we know that xy : yz = 1:2 Take xy : yz and divide both sides by y to get the EQUIVALENT ratio x:z This means x:z = 1:2 Check the answer choices... A. 2 : 3 : 6 this answer choice says x:z = 2:6. We need x:z = 1:2 ELIMINATE A ...” Yesterday Brent@GMATPrepNow posted a reply to Over a four-game stretch, Dennis's bowling scope average 240 in the Problem Solving forum “In other words, an increase from 240 to 300 represents what kind of percent increase? Percent increase = (100)(new - old)/old = (100)(300 - 240)/240 = (100)(60)/240 = (100)(1/4) = 25% Answer: B Cheers, Brent” Yesterday Rich.C@EMPOWERgmat.com posted a reply to GMAT Prep Experience with EMPOWERgmat in the I just Beat The GMAT! forum “Hi Shubrat, That''s FANTASTIC news! With this 690, you can apply to any Schools that interest you (and it sounds as if this score puts you above the average Scores at the Programs that you''re considering - which is great news). I hope you reach out and let us know how your applications go. We ...” Yesterday Rich.C@EMPOWERgmat.com posted a reply to retake gmat in the GMAT Strategy forum “Hi Sarat, Studying 12 hours a day would probably be too much studying - and would likely lead to an increased chance of ''burning out'' before your Exam (and that is something that we want to avoid). If you want to study 6-8 hours a day, then that would probably be fine - but you must build in ...” Yesterday Rich.C@EMPOWERgmat.com posted a reply to Self Study Materials - All Areas - 4 month preparation in the GMAT Strategy forum “Hi Gopi, To start, a 570 is a strong ''baseline'' score (the average score on the Official GMAT hovers around 550 most years). You''ve also given yourself plenty of time to study - which is good. Given your Score Goal, you would likely find it beneficial to invest in a GMAT Course of some type ...” Yesterday Brent@GMATPrepNow posted a reply to The table above shows the distribution of tests scores for a in the Problem Solving forum “Since we have an ODD number of values, the median will be the MIDDLEMOST value. In other words, if we arrange all 73 values in ASCENDING order, the median will be the 37th value (i.e., 36 values are below and 36 values are above). The table says the first 2 scores in the 50-59 range. So, the 1st ...” Yesterday Brent@GMATPrepNow posted a reply to # X-Axis Intercepts in the Problem Solving forum “Let''s find some points that lie on each of the curves. So, for each equation, we''ll find a pair of values (an x-value and a y-value) that satisfy each equation. We''ll do so by plugging in some x-values and calculating the corresponding y-values. Let''s start with x = 0 Plug x = 0 into ...” November 14, 2018 Brent@GMATPrepNow posted a reply to How many positive two-digit numbers yield a remainder of 1 in the Problem Solving forum “When it comes to remainders, we have a nice rule that says: If N divided by D leaves remainder R, then the possible values of N are R, R+D, R+2D, R+3D,. . . etc. For example, if k divided by 5 leaves a remainder of 1, then the possible values of k are: 1, 1+5, 1+(2)(5), 1+(3)(5), ...” November 14, 2018 Rich.C@EMPOWERgmat.com posted a reply to Distance Problem in the Problem Solving forum “Hi All, We''re told that A, B and C each drive 100-mile legs of a 300-mile course at speeds of 40, 50 and 60 miles per hour, respectively. We''re asked what FRACTION of the total drive time did A drive. This question can be solved in a couple of different ways; there''s actually a great ''ratio ...” November 13, 2018 Rich.C@EMPOWERgmat.com posted a reply to Paul sells encyclopedias door-to-door. He earns$160 on in the Problem Solving forum
“Hi All, We''re told that Paul sells encyclopedias door-to-door. He earns $160 on every paycheck, regardless of how many sets he sells and a commission as follows: 10% on the first$10,000.00 and 5% for any additional sales beyond that. His largest paycheck of the year was $1,320. We''re ...” November 13, 2018 Rich.C@EMPOWERgmat.com posted a reply to On a wedding catering service, An experienced chef can in the Problem Solving forum “Hi All, We''re told that on a wedding catering service, an experienced chef can prepare a service for a wedding in 8 hours while an novice chef would finish the preparations in 12 hours. If the catering service employs the SAME number of novice and experienced chefs, then how many chefs would it ...” November 13, 2018 Rich.C@EMPOWERgmat.com posted a reply to GMATPrep in the Problem Solving forum “Hi All, We''re told that 3^(X) - 3^(X-1) = 162. We''re asked for the value of then (X)(X-1). This question can be solved rather easily with a bit of ''brute force'' arithmetic. Since we''re dealing with ''powers of 3'', let''s map out the first several values: 3^1 = 3 3^2 = 9 3^3 = 27 3^4 ...” November 13, 2018 Rich.C@EMPOWERgmat.com posted a reply to The ratio of the degree measures of the angles of a triangle in the Problem Solving forum “Hi All, We''re told that the ratio of the degree measures of the angles of a triangle is 2:3:4. We''re asked which of the following is the sum of the degree measures of the SMALLEST and LARGEST angles. Since the ratio of the angles is 2:3:4, we can refer to those 3 angles as 2X, 3X and 4X, ...” November 13, 2018 Rich.C@EMPOWERgmat.com posted a reply to When Leo imported a certain item, he paid a 7 percent import in the Problem Solving forum “Hi All, You can approach this question by TESTing THE ANSWERS. Instead of setting this up algebraically, you can use the ''spread'' of the answer choices to your advantage. Here, if the total value of the item were$2,000, then the tax would only apply to the amount over $1,000....$1,000 x ...”
November 13, 2018
Rich.C@EMPOWERgmat.com posted a reply to A chemical supply company has 60 liters of a 40% HNO3 in the Problem Solving forum
“Hi swerve, We''re told that a chemical supply company has 60 liters of a 40% HNO3 solution. We''re asked for the number of liters of pure undiluted (meaning 100%) HNO3 the chemists must add so that the resultant solution is a 50% solution. This question is essentially a ''Weighted Average'' ...”
November 13, 2018
Brent@GMATPrepNow posted a reply to When Leo imported a certain item, he paid a 7 percent import in the Problem Solving forum
“Here''s a step-by-step algebraic solution. Let T = the TOTAL value of the item. Leo paid a 7% import tax on the portion of the total value of the item in EXCESS of $1000 So, Leo pays tax on the amount that''s GREATER then$1000 So, Leo pays 7% tax on (T - 1000) We can write: import tax = ...”
November 13, 2018
Brent@GMATPrepNow posted a reply to If xy ≠ 0 and x^2+4y^2=4xy, (x+y)/(x-y)=? in the Problem Solving forum
“GIVEN: x² + 4y² = 4xy Subtract 4xy from both sides to get: x² - 4xy + 4y² = 0 Factor left side to get: (x - 2y)(x - 2y) = 0 So, we can conclude that (x - 2y) = 0, which means x = 2y Now take (x+y)/(x-y) and replace x with 2y to get: (x + y)/(x - y) = (2y + y)/(2y - y) = 3y/y = 3 ...”
November 13, 2018
Rich.C@EMPOWERgmat.com posted a reply to During the four years that Mrs. Lopez owned her car, she in the Problem Solving forum
“Hi All, While this question IS wordy, the math behind it is just arithmetic. If you break the prompt into ''pieces'', then the work shouldn''t be too difficult. The first two sentences tell us that the total car expenses were $18,000, fuel and maintenance costs accounted for 1/3 of THAT total and ...” November 12, 2018 Rich.C@EMPOWERgmat.com posted a reply to 490 to 740, Verbal 45 - The GMAT Crush Fest in the I just Beat The GMAT! forum “Hi clubber112358, You might find it useful to start your own post-thread (instead of piggy-backing on this one) and providing a more-detailed description of how you''ve been studying. If you would rather keep the discussion private, then you can feel free to PM or email me directly. Before I ...” November 12, 2018 Rich.C@EMPOWERgmat.com posted a reply to retake gmat in the GMAT Strategy forum “Hi sarat0994, From what you have described, it sounds as if you worked through lots of practice questions, but it''s not clear whether you were actually practicing Tactics and training to take advantage of all of the built-in patterns that GMAT question-writers put into the Exam or not. Raising ...” November 12, 2018 Rich.C@EMPOWERgmat.com posted a reply to [ADVICE IS WELCOME!] Post GMAT Debrief in the GMAT Strategy forum “Hi Leo, To start, since you have named some highly-competitive Schools, you would likely find it beneficial to speak with an Admissions Expert about your overall profile and application plans. There''s a Forum full of those Experts here: ...” November 12, 2018 Brent@GMATPrepNow posted a reply to OG #217 question in the Problem Solving forum “P(selecting a sibling pair) = P(select a junior with a sibling AND select the senior who is that junior''s sibling) = P(select a junior with a sibling) x P(select the senior who is that junior''s siblingx 1/800 = 60/800,000 = 3/40,000 = A Note: P(select a junior with a sibling) = 60/1000, ...” November 12, 2018 Brent@GMATPrepNow posted a reply to In the figure AB and CD are two diameters of circle. in the Problem Solving forum “Let''s use some useful circle properties First let''s add a blue line, to divide ∠CEB into 2 angles https://i.imgur.com/xe05QIU.png CD is the DIAMETER of the circle Since ∠CED is an inscribed angle containing (aka "holding") the diameter, we can conclude that ∠CED = 90° ...” November 12, 2018 Brent@GMATPrepNow posted a reply to Is the tallest child in Class A taller than tallest child in in the Data Sufficiency forum “Target question: Is the tallest child in Class A is taller than tallest child in Class B? Jump to . . . Statements 1 and 2 COMBINED There are several scenarios that satisfy BOTH statements. Here are two: Case a: Class A heights = {1, 50} and Class B heights = {2, 40}. In this case, the ...” November 12, 2018 Rich.C@EMPOWERgmat.com posted a reply to A gardener is going to plant 2 red rosebushes and 2 white in the Problem Solving forum “Hi All, The math that''s required to answer this question can actually be done in a couple of different ways, depending on how you "see" probability questions. We''re given 2 red rosebushes (R1 and R2) and two white rosebushes (W1 and W2). We''re told to put these 4 rosebushes in a ...” November 11, 2018 Rich.C@EMPOWERgmat.com posted a reply to Veritas Prep: is it significantly harder than others? in the GMAT Strategy forum “Hi baldururikson, The scoring algorithm on the Official GMAT is far more complicated than most people realize. Since that algorithm is proprietary, no GMAT company has an exact match for it, thus CAT scores can vary a bit based on the ''biases'' involved in their respective designs. The most ...” November 11, 2018 Rich.C@EMPOWERgmat.com posted a reply to 12 year out of college, GMAT study plans? in the GMAT Strategy forum “Hi KDR83, First off, a 640 is a solid score (it''s right around the 70th percentile overall), so it could be enough to get you into your first-choice School. As such, a retest might not be necessary. Depending on the Schools that you plan to apply to, you would likely find it beneficial to speak ...” November 11, 2018 Rich.C@EMPOWERgmat.com posted a reply to Feel Demotivated in the The GMAT Avengers Study Group forum “Hi Arun192097, Since this website is devoted to preparing for the GMAT and applying to Business School, we should focus on those areas of discussion. Before I can offer you the specific advice that you’re looking for, it would help if you could provide a bit more information on how you''ve ...” November 11, 2018 Rich.C@EMPOWERgmat.com posted a reply to retake gmat in the GMAT Strategy forum “Hi sarat0994, I''m sorry to hear that Test Day did not go as well as hoped. The ''swings'' in your practice CAT/mock Scores imply that you might have taken those Exams in an inconsistent fashion - and in ways that did not necessarily ''match up'' with what you faced on Test Day. Before we ...” November 11, 2018 Brent@GMATPrepNow posted a reply to Eight women and two men are available to serve on a in the Problem Solving forum “When it comes to probability questions involving "at least," it''s best to try using the complement. That is, P(Event A happening) = 1 - P(Event A not happening) So, here we get: P(getting at least 1 man) = 1 - P(not getting at least 1 man) What does it mean to not get at least 1 man? ...” November 11, 2018 Brent@GMATPrepNow posted a reply to If the positive integer n is greater than 6, what is the in the Data Sufficiency forum “Here''s a somewhat long approach (but it works!): Target question: What is the remainder when n is divided by 6? Given: Positive integer n is greater than 6 Statement 1: When n is divided by 9, the remainder is 2. ------ASIDE---------------- When it comes to remainders, we have a ...” November 11, 2018 Brent@GMATPrepNow posted a reply to If x and y are positive integers, what is the remainder when in the Data Sufficiency forum “Hi Swerve, To avoid ambiguity, you might want to add some spaces or brackets to the original expression. As it stands, 10^x+y could be interpreted as either 10^(x+y) or (10^x) + y Cheers, Brent” November 11, 2018 Brent@GMATPrepNow posted a reply to If x and y are positive integers such that x = 8y + 12, what in the Data Sufficiency forum “Target question: What is the greatest common divisor of x and y? Given: x = 8y + 12 Statement 1: x = 12u, where u is an integer. There are several pairs of values that satisfy the given conditions. Here are two: Case a: x=36 and y=3, in which case the GCD of x and y is 3 Case b: x=60 ...” November 11, 2018 Brent@GMATPrepNow posted a reply to Which of the following is closest to the value of (2^23) in the Problem Solving forum “(2^23)(5^26) = (2^23)(5^23)(5^3) = (2^23)(5^23)(5^3) = (10^23)(5^3) = (10^23)(125) ≈ (10^23)(100) ≈(10^23)(10^2) ≈10^25 Answer: C Cheers, Brent” November 11, 2018 Brent@GMATPrepNow posted a reply to A gardener is going to plant 2 red rosebushes and 2 white in the Problem Solving forum “We can also apply probability rules: P(2 middle bushes are red) = P(1st bush is white AND 2nd bush is red AND 3rd bush is red AND 4th bush is white) = P(1st bush is white) x P(2nd bush is red) x P(3rd bush is red) x P(4th bush is white) = 2/4 x 2/3 x 1/2 x 1/1 = 1/6 = B Cheers, Brent” November 11, 2018 Brent@GMATPrepNow posted a reply to A gardener is going to plant 2 red rosebushes and 2 white in the Problem Solving forum “As with many probability questions, we can also solve this using counting techniques. P(2 middle are red) = (# of outcomes with 2 red in middle)/(total number of outcomes) Label the 4 bushes as W1, W2, R1, R2 total number of outcomes We have 4 plants, so we can arrange them in 4! ways = ...” November 11, 2018 Brent@GMATPrepNow posted a reply to Of the first three dozen cookies baked at a bake shop on a in the Data Sufficiency forum “ Given: Of the first three dozen (36) cookies baked at a bake shop on a certain day, 1/3 were chocolate chip cookies. 1/2 of the remaining cookies that were baked that day were chocolate chip cookies, 1/3 of 36 = 12. So, 12 chocolate cookies were baked in the first round of baking. Let x = ...” November 10, 2018 Brent@GMATPrepNow posted a reply to There were 36,000 hardback copies of a certain novel sold in the Problem Solving forum “From the time the first paperback copy was sold until the last copy of the novel was sold 9 times as many paperback copies as hardback copies were sold Let x = number of hardback copies sold during this time So 9x = number of paperback copies sold during this time So, x + 9x = total number of ...” November 10, 2018 Brent@GMATPrepNow posted a reply to A box contains 10 balls numbered from 1 to 10 inclusive. If in the Problem Solving forum “P(Ann and Jane remove same ball) = P(Ann removes ANY ball AND Jane''s ball matches Ann''s ball) = P(Ann removes ANY ball) x P(Jane''s ball matches Ann''s ball) = 1 x 1/10 = 1/10 Answer: D Aside: Once Jane removes her ball (and then replaces it), we have 10 balls, and 1 of them is the one ...” November 10, 2018 Brent@GMATPrepNow posted a reply to If CD = 6, what is the length of BC? in the Data Sufficiency forum “Is there an image? Cheers, Brent” November 9, 2018 Brent@GMATPrepNow posted a reply to Andrew has a certain number of coins in his pocket. He has in the Problem Solving forum “Let x = number of QUARTERS in pocket So, 0.25x = VALUE of quarters in pocket He has three times as many dimes as quarters So, 3x = number of DIMES in pocket So, 0.10(3x) = 0.3x = VALUE of dimes in pocket He has six times as many nickels as dimes. So, (6)(3x) = number of NICKELS in ...” November 8, 2018 Brent@GMATPrepNow posted a reply to Challenge: Al, Bob, Cal and Don each own 1 hat. If the 4... in the Problem Solving forum “I created this question to highlight many students'' tendency to avoid listing and counting as a possible approach. As you''ll see, the approach is probably the fastest approach. P(no one receives his own hat) = (# of outcomes in which no one receives his own hat)/(TOTAL number of outcomes) ...” November 8, 2018 Brent@GMATPrepNow posted a reply to There are 27 different three-digit integers that can be in the Problem Solving forum “Yes, great work, Mitch! I thought I''d mention that, once we know the correct answer is a multiple of 222 (which is also a multiple of 3), then the correct answer will be a multiple of 3. Useful property: If a number is a multiple of 3, then the sum of its digits is also a multiple of 3. When we ...” November 7, 2018 Brent@GMATPrepNow posted a new topic called Challenge: Al, Bob, Cal and Don each own 1 hat. If the 4... in the Problem Solving forum “Al, Bob, Cal and Don each own 1 hat. If the 4 hats are randomly distributed so that each man receives exactly 1 hat, what is the probability that no one receives his own hat? A) 1/8 B) 1/4 C) 1/3 D) 3/8 E) 1/2 Answer: D Difficulty level: 650 – 700 Source: www.gmatprepnow.com” November 7, 2018 Brent@GMATPrepNow posted a reply to If x, y and z are non-negative integers such that x < y & in the Problem Solving forum “I created this question to show that there can be times when the best (i.e., fastest) way to solve a counting question is by listing and counting How do we know when it''s not a bad idea to use listing and counting? The answer choices will tell us (ALWAYS scan the answer choices before ...” November 7, 2018 Brent@GMATPrepNow posted a reply to How many men are in a certain company's vanpool program? in the Data Sufficiency forum “Target question: How many men are in a certain company''s vanpool program? Statement 1: The ratio of men to women in the program is 3 to 2. Let''s TEST some values. There are several scenarios that satisfy statement 1. Here are two: Case a: There are 3 men and 2 women in the program. In ...” November 7, 2018 Brent@GMATPrepNow posted a reply to Speed Time Distance MGMAT in the Problem Solving forum “GIVEN: When the men start walking, Brian has a 30-mile lead Let B = Brian''s walking speed (in miles per hour) Let A = Ashok''s walking speed (in miles per hour) Since Ashok''s speed is greater than Brian''s speed, the rate at which the gap shrinks = (A - B) miles per hour For example, if A ...” November 6, 2018 Brent@GMATPrepNow posted a reply to 2019 GMAC Official Guide applicable for 60-Day Study Guide? in the The 60-Day GMAT Study Guide forum “If you go here (https://www.gmatprepnow.com/content/improvement-chart) and download the Improvement Chart for the OG2016, you''ll see the question breakdown for each topic. This should help. Cheers, Brent” November 6, 2018 Brent@GMATPrepNow posted a reply to In a certain game, a large bag is filled with blue, green, in the Problem Solving forum “This question begs for some prime factorization. 88,000 = (2)(2)(2)(2)(2)(2)(5)(5)(5)(11) First, we can see that there must be one (11-point) red chip. Now, what role do these 2''s play? Since there are no 2''s hiding among the 5-point chips or the 11-point chips, the 2''s must be associated ...” November 6, 2018 Brent@GMATPrepNow posted a reply to [x] is the greatest integer less than or equal x, what is th in the Problem Solving forum “GIVEN: For example, [3.2] = 3, since 3 is the greatest integer that is less than (or equal) to 3.2 Likewise, [8.7] = 8, since 8 is the greatest integer that is less than (or equal to) 8.7 Now onto the question.... √25 = 5 √36 = 6 √49= 7 √64 = 8 Since √30 is BETWEEN √25 ...” November 6, 2018 Brent@GMATPrepNow posted a reply to If in k+1 years from now John will be m years old, then how in the Problem Solving forum “In k+1 years from now John will be m years old So, m - (k + 1) = John''s PRESENT age How old was John t-1 years ago? So, m - (k + 1) - (t - 1) = John''s age (t-1) YEARS AGO Simplify m - (k + 1) - (t - 1) to get: m - k - t Answer: A Cheers, Brent” November 6, 2018 Brent@GMATPrepNow posted a reply to Pipe A runs 30 liters of water per minute into a pool that in the Problem Solving forum “Let''s determine the COMBINED RATE of the two pipes Given: Pipe A''s RATE = 30 liters per minute This is equivalent to 1800 liters per HOUR Pipe B fills a third of the pool in 6 hours So, Pipe B fills the ENTIRE pool (3600 liters) in 18 hours Rate = Output/time = 3600/18 = 200 liters ...” November 6, 2018 Brent@GMATPrepNow posted a new topic called If x, y and z are non-negative integers such that x < y < z, in the Problem Solving forum “If x, y and z are non-negative integers such that x < y < z, then the equation x + y + z = 11 has how many distinct solutions? A) 5 B) 10 C) 11 D) 22 E) 78 Answer: B Difficulty level: 600-650 Source: www.gmatprepnow.com” November 5, 2018 Brent@GMATPrepNow posted a reply to Challenge question: Is |1 - 4k| < k? in the Data Sufficiency forum “Target question: Is |1 - 4k| < k? Statement 1: k > 4x³ This pretty much tells is that k can have ANY value. For example, notice that, if x = -100, then 4x³ = -4,000,000 So, for this value of x, k can be any number greater than -4,000,000 Let''s TEST some values. There are ...” November 5, 2018 Brent@GMATPrepNow posted a reply to Which sport utility vehicle has a higher list price, the in the Data Sufficiency forum “Target question: Which sport utility vehicle has a higher list price, the Touristo of the Leisure? Statement 1: The list price of the Leisure is 5/6 the list price of the Touristo. If the Leisure''s price is 5/6 of the Touristo''s price, then the answer to the target question is the Touristo ...” November 5, 2018 Brent@GMATPrepNow posted a reply to Bite-sized video lessons from GMAT Prep Now in the GMAT Math forum “Here''s our video on Range and Standard Deviation https://www.youtube.com/watch?v=FbAlIjw2fwY Cheers, Brent” November 5, 2018 Brent@GMATPrepNow posted a reply to If xy=-18, is x less than y? in the Data Sufficiency forum “ Given: xy = -18 Target question: is x less than y? Statement 1: x < 0 In other words, x is NEGATIVE So, our given information (xy = -18) becomes: (NEGATIVE)(y) = -18 In other words: (NEGATIVE)(y) = NEGATIVE This tells us that y is POSITIVE If y is POSITIVE, and x is NEGATIVE, the ...” November 4, 2018 Brent@GMATPrepNow posted a reply to Challenge #2: If x and y are different positive integers, wh in the Problem Solving forum “i) When x is divided by y, the remainder is 2x The remainder cannot be greater than the dividend (the number we''re dividing) For example, it CANNOT be the case that 17 divided by 5 leaves a remainder of 34 Statement i can never be true Check the answer choices. . . . ELIMINATE A and D ii) ...” November 3, 2018 Brent@GMATPrepNow posted a new topic called Challenge question: Is |1 - 4k| < k? in the Data Sufficiency forum “Is |1 - 4k| < k? (1) k > 4x³ (2) k < 2x – x² - 2 Answer: B Difficulty level: 700+ Source: www.gmatprepnow.com” November 3, 2018 Rich.C@EMPOWERgmat.com posted a reply to A post on a website gains a point if a user choose to in the Problem Solving forum “Hi All, We''re told that a post on a website gains a point if a user chooses to upvote it and loses a point if a user chooses to downvote it and that a particular post has a total of 60 points (with 40% of the votes being downvotes). We''re asked for the total number of votes that have been cast ...” November 2, 2018 Rich.C@EMPOWERgmat.com posted a reply to The hexagonal face of the in the Problem Solving forum “Hi All, We''re told that the hexagonal face of the block shown in the figure above has sides of equal length and angles of equal measure and each lateral face is rectangular. We''re asked for the area, in square inches, of one lateral face. This question is based on a Geometry pattern - and if ...” November 2, 2018 Rich.C@EMPOWERgmat.com posted a reply to Cars J and K are making the trip from City A to City B. in the Problem Solving forum “Hi All, We''re told that Cars J and K are making the trip from City A to City B. Car J departs from City A 15 minutes AFTER Car K does, both cars travel along the same route and Car K travels at a constant speed that is 80% the constant speed of Car J. We''re asked for the number of MINUTES that ...” November 2, 2018 Brent@GMATPrepNow posted a reply to If the average (arithmetic mean) of p, q, and r is 6, what i in the Data Sufficiency forum “ Given: The average (arithmetic mean) of p, q, and r is 6 We can write: (p + q + r)/3 = 6 This means: p + q + r = 18 Target question: What is the value of r? Statement 1: p = -r Given: p + q + r = 18 Replace p with -r to get: -r + q + r = 18 Simplify: q = 18 What about the value of ...” November 2, 2018 Brent@GMATPrepNow posted a reply to Cars J and K are making the trip from City A to City B. in the Problem Solving forum “Car K travels at a constant speed that is 80% the constant speed of Car J Let''s assign some nice values to the speeds. Let''s say Car J travels 40 miles per hour So, Car K travels 32 miles per hour Car J departs from City A 15 minutes after Car K does Let''s calculate the distance that Car ...” November 2, 2018 Brent@GMATPrepNow posted a reply to At a family summer party, each of the x members of the in the Problem Solving forum “Let''s use the INPUT-OUTPUT approach. It might be useful to choose a number that works well with the fractions given in the question (1/3 and 1/7). So, let''s say there are 21 family members at the party. In other words, we''re saying that x = 21 1/3 chose to have a hamburger, and of ...” November 1, 2018 Brent@GMATPrepNow posted a reply to When a positive integer n is divided by 19, what is the rema in the Data Sufficiency forum “Target question: When n is divided by 19, what is the remainder? Statement 1: n-17 is a multiple of 19 ----ASIDE------------------------------------------- If N is a multiple of d, then we can write N = dk (for some integer k) For example, if N is a multiple of 5, then we can write N = 5k ...” November 1, 2018 Brent@GMATPrepNow posted a reply to In the diagram above, points A, B, C, D, and E represent the in the Problem Solving forum “points A, B, C, D, and E represent the five teams in a certain league in which each team must play each of the other teams exactly once. Let''s first determine the total number of games that will be played. There are 5 teams, so each team will play 4 games (since a team can''t play itself) So, ...” November 1, 2018 Brent@GMATPrepNow posted a reply to In four years, Andy will be twice as old as Betsy. How old in the Data Sufficiency forum “ Given: In four years, Andy will be twice as old as Betsy. Let A = Andy''s PRESENT age Let B = Betsy''s PRESENT age So, A+4 = Andy''s age IN 4 YEARS And so, B+4 = Betsy''s age IN 4 YEARS If Andy will be twice as old as Betsy IN 4 YEARS, we can write: A+4 = 2(B+4) Expand: A + 4 = 2B + 8 ...” October 31, 2018 Brent@GMATPrepNow posted a reply to If m and n are integers, is m+m^2-n an even number? in the Data Sufficiency forum “ Given: m and n are integers Target question: Is m + m² - n an even number? This is a good candidate for rephrasing the target question Aside: Here’s a video with tips on rephrasing the target question: We can take the expression, m + m² - n and rewrite it as m(1 + m) - n Now notice ...” October 31, 2018 Brent@GMATPrepNow posted a reply to In 1995 a certain store had 1,800 tools in stock that had in the Problem Solving forum “1,000 of these tools were sold in 1995 for$40 each So, the REVENUE = (1000)($40) =$40,000 The 1000 tools were purchased for $30 each. So, the EXPENSE = (1000)($30) = $30,000 PROFIT for 1995 =$40,000 - $30,000 =$10,000 ----------------------------------------------- The remaining 800 ...”
October 31, 2018
Brent@GMATPrepNow posted a reply to Tom, Bill, Robert, Roger, and Terry are standing in a row in the Problem Solving forum
“One approach is to ignore the rule and determine the total number of ways to arrange all 5 people, and then subtract the number of arrangements that BREAK the rule. I''m sure someone will post that kind of solution shortly. Here''s another approach: Take the task of arranging the 5 men and ...”
October 30, 2018
Brent@GMATPrepNow posted a new topic called Challenge #2: If x and y are different positive integers, wh in the Problem Solving forum
“If x and y are different positive integers, which of the following COULD be true: i) When x is divided by y, the remainder is 2x ii) When x is divided by 2y, the remainder is y iii) When (2x + y) is divided by (x + y), the remainder is y A) i only B) ii only C) iii only D) i & ii ...”
October 30, 2018
Brent@GMATPrepNow posted a reply to Challenge: If x and y are different positive integers, which in the Problem Solving forum
“i) When x is divided by y, the remainder is x This occurs any time x < y For example, if x = 5 and y = 7, then statement i becomes: When 5 is divided by 7, the remainder is 5 So true! Scan the answer choices....eliminate D ----------------------------------------------------- ii) When 2x ...”
October 30, 2018
Brent@GMATPrepNow posted a reply to Carmelo and LeBron participate in a seven-person footrace on in the Problem Solving forum
“Here are three similar questions to practice with: - http://www.beatthegmat.com/counting-six-mobsters-t47167.html - http://www.beatthegmat.com/permutation-and-combination-t273916.html - http://www.beatthegmat.com/permutations-with-waiting-line-t274020.html Cheers, Brent”
October 30, 2018
Brent@GMATPrepNow posted a reply to A certain basket contains 10 apples, 7 of which are red and in the Problem Solving forum
“Jay has demonstrated a solution that involves counting techniques. Here''s one that involves probability rules. Let''s find the probability of selecting a red apple 1st, a red apple 2nd, and a green apple 3rd (aka RRG) P(red apple 1st AND red apple 2nd AND green apple 3rd) = P(red apple 1st) x ...”
October 30, 2018
Brent@GMATPrepNow posted a reply to A salesperson for an automobile dealer earns an annual in the Problem Solving forum
“Total earnings = (base salary) + (commission) base salary = $25,000 commission = 10% of total sales OVER$100,000 = 10% of (x - $100,000) = 0.1(x -$100,000) So, total earnings = $25,000 + 0.1(x -$100,000) Answer: E Cheers, Brent”
October 30, 2018
Brent@GMATPrepNow posted a reply to There are 16 teams in a soccer league, and team plays each in the Problem Solving forum
“Another approach: The question is really asking, "In how many different ways can we create 2-team pairings from 16 teams?" Since the order of the selections does not matter (i.e., selecting teams A and B to play, is the same as selecting teams B and A to play), we can use combinations. ...”
October 30, 2018
Brent@GMATPrepNow posted a reply to There are 16 teams in a soccer league, and team plays each in the Problem Solving forum
“There are 16 teams. If we ask each team, "How many teams did you play?" we''ll find that each team played 15 teams, which gives us a total of 240 games (since 16 x 15 = 240). From here we need to recognize that each game has been COUNTED TWICE. For example, if Team A and Team B play ...”
October 30, 2018
Rich.C@EMPOWERgmat.com posted a reply to The figure above represents a rectangular garden bordered by in the Data Sufficiency forum
“Hi All, We''re told that the figure above represents a rectangular garden bordered by a walkway that has a uniform width of 3 feet. We''re asked for the PERIMETER of the garden. This question can be solved with a mix of Arithmetic and TESTing VALUES. 1) The outer perimeter of the walkway is ...”
October 29, 2018
Rich.C@EMPOWERgmat.com posted a reply to Economist Gmat Tutor review in the The GMAT Avengers Study Group forum
“Hi saurabh_sha, From your post, it sounds like you''re just starting out. Is that true? Have you done any studying for the GMAT so far? If you have, then what materials have you used and how have you scored on your practice CATs/mocks? If you''re just beginning, then it would be a good idea to ...”
October 29, 2018
Brent@GMATPrepNow posted a reply to For integers a, b, c, a/(b - c)=1 what is the value of (b-c) in the Data Sufficiency forum
“ Given: a/(b - c) = 1 Target question: What is the value of (b-c)/b ? This is a good candidate for rephrasing the target question. Aside: Here’s a video with tips on rephrasing the target question: If a/(b - c) = 1, then we know that a = b - c The target question asks "What is the ...”
October 29, 2018
Brent@GMATPrepNow posted a reply to If a and b are integers such that a > b > 1, which of in the Problem Solving forum
“Let''s make an important observation. Some positive multiples of 3 are: 3, 6, 9, 12, . . . . Some positive multiples of 5 are: 5, 10, 15, 20, . . . . Some positive multiples of 12 are: 12, 24, 36, 48, . . . . General observation: the positive multiples of k are all greater than or equal to k ...”
October 29, 2018
Brent@GMATPrepNow posted a new topic called Challenge: If x and y are different positive integers, which in the Problem Solving forum
“If x and y are different positive integers, which of the following COULD be true: i) When x is divided by y, the remainder is x ii) When 2x is divided by y, the remainder is x iii) When x+y is divided by x , the remainder is x-y A) i only B) i & ii only C) i & iii only D) ii & ...”
October 29, 2018
Brent@GMATPrepNow posted a reply to What is the value of x? in the Data Sufficiency forum
“Target question: What is the value of x? Statement 1: (x + 2)(x + 3) = 0 This means that EITHER x = -2 OR x = -3 Since we cannot answer the target question with certainty, statement 1 is NOT SUFFICIENT Statement 2: x² + 5x + 6 = 0 Factor the left side of the equation to get: (x + 2)(x ...”
October 29, 2018
Rich.C@EMPOWERgmat.com posted a reply to If a certain wheel turns at a constant rate of x revolutions in the Problem Solving forum
“Hi All, We''re told that a certain wheel turns at a constant rate of X revolutions per MINUTE. We''re asked for the number of revolutions that the wheel will make in K SECONDS. This question can be solved in a number of different ways, including by TESTing VALUES. IF.... X=2 and K=60... The ...”
October 29, 2018
Rich.C@EMPOWERgmat.com posted a reply to Jonah drove the first half of a 100-mile trip in x hours and in the Problem Solving forum
“Hi All, We''re told that Jonah drove the first half of a 100-mile trip in X hours and the second half in Y hours. We''re asked which of the following is equal to Jonah’s average speed, in miles per hour, for the entire trip. This question can be solved in a couple of different ways, including ...”
October 29, 2018
Rich.C@EMPOWERgmat.com posted a reply to If a and b are integers such that a > b > 1, which of in the Problem Solving forum
“Hi All, We''re told that A and B are integers such that A > B > 1. We''re asked which of the following CANNOT be a multiple of either A or B. This question can be solved with some basic concept knowledge of the rules behind ''multiples.'' With the exception of "0", multiples ...”
October 29, 2018
Rich.C@EMPOWERgmat.com posted a reply to Both car A and car B set out from their original locations in the Problem Solving forum
“Hi All, We''re told that both car A and car B set out from their original locations at exactly the SAME time and on exactly the SAME route. Car A drives from Morse to Houston at an average speed of 65 miles per hour and Car B drives from Houston to Morse at 50 miles per hour, and then ...”
October 29, 2018
Rich.C@EMPOWERgmat.com posted a reply to The average age of a group of n people is 15 yrs. One more in the Problem Solving forum
“Hi All, We''re told that the average age of a group of N people is 15 yrs and when one more person aged 39 joins the group, the new average is 17 yrs. We''re asked for the value of N. This question can be solved in a number of different ways, including with a bit of ''number logic'' and a little ...”
October 29, 2018
Brent@GMATPrepNow posted a reply to A length of rope is cut into three different lengths. What in the Data Sufficiency forum
“Target question: What is the length of the shortest rope? Let''s assign some variables. Let x = length of shortest rope Let y = length of middle rope Let z = length of longest rope Statement 1: The combined length of the longest two pieces is 6 feet. In other words, y + z = 6 Since we ...”
October 28, 2018
Brent@GMATPrepNow posted a reply to Challenge question: At noon, Joe and a hummingbird leave in the Problem Solving forum
“The main idea here is that all 3 travelers travel for the SAME amount of time. So, let''s first determine the time it takes for Joe and Sue to meet. This is a shrinking gap question. To determine the rate at which the gap shrinks, we''ll ADD the travel speeds of Joe and Sue That is, ...”
October 28, 2018
Brent@GMATPrepNow posted a reply to If x and y are positive, what is the value of y ? in the Data Sufficiency forum
“Target question: What is the value of y? Given: x and y are positive Statement 1: xy is the square of an integer. There are several values of x and y that satisfy this condition. Here are two: Case a: x = 1 and y = 1. Here xy = (1)(1) = 1, which is the square of an integer. In this ...”
October 28, 2018
Brent@GMATPrepNow posted a new topic called Challenge question: At noon, Joe and a hummingbird leave in the Problem Solving forum
“At noon, Joe and a hummingbird leave point A and travel towards point B, which is 12 miles away. At the same time Sue leaves point B and travels toward point A. Joe, Sue and the hummingbird travel at constant speeds of 3 miles per hour, 4 miles per hour, and 84 miles per hour respectively. When the ...”
October 27, 2018
Brent@GMATPrepNow posted a reply to There are n students in a class. Of them, k boys and k girls in the Data Sufficiency forum
“Target question: What is the probability that Harvey will be paired with Jessica? Given: There are n students in a class. Of them, k boys and k girls (including Harvey and Jessica) are selected for a dance performance in which students will dance in pairs of one boy and one girl. ...”
October 27, 2018
Brent@GMATPrepNow posted a reply to When the positive integer n is divided by 25, the remainder in the Data Sufficiency forum
“Target question: What is the value of n? Given: When the positive integer n is divided by 25, the remainder is 13. -------ASIDE------------- When it comes to remainders, we have a nice rule that says: If N divided by D leaves remainder R, then the possible values of N are R, R+D, R+2D, ...”
October 27, 2018
Brent@GMATPrepNow posted a reply to A circus clown is entertaining kids by making balloon in the Problem Solving forum
“As with many probability questions, we can solve this by using counting techniques or rules of probability. Let''s use rules of probability P(balloon animal is an elephant) = 1/4 P(balloon animal is purple) = 1/5 P(clown makes a purple elephant balloon animal) = P(balloon animal is ...”
October 27, 2018
Brent@GMATPrepNow posted a reply to In a right triangle, the longer leg is two more than three in the Problem Solving forum
“In a right triangle, the longest side is called the hypotenuse, and the two sides that meet to create a 90-degree angle are called the legs. So, one leg will be the triangle''s base, and the other leg will be the triangle''s height. Let x = length of the triangle''s base (which, for this ...”
October 27, 2018
Brent@GMATPrepNow posted a reply to If a and b are two positive numbers, what is the product of in the Data Sufficiency forum
“Target question: What is the value of ab? Statement 1: The LCM of a and b is 16 Let''s TEST some values. There are several values of a and b that satisfy statement 1. Here are two: Case a: a = 1 and b = 16 (the LCM of 1 and 16 is 16). In this case, the answer to the target question is ab = ...”
October 26, 2018
Brent@GMATPrepNow posted a reply to In the mid-1960's a newly installed radar warning system in the Sentence Correction forum
“The idiom here is "Mistake x FOR y" So, we can eliminate A, C and E We''re left with B and D D conveys an ambiguous message, because it suggests that the moon was rising for an attack. ELIMINATE D Answer: B Cheers, Brent”
October 26, 2018
Brent@GMATPrepNow posted a reply to What is the largest prime factor of the expression 3^8 − 2 in the Problem Solving forum
“There''s a difference of squares "hiding" in the expression 3^8 − 2^12 That is 3^8 − 2^12 = (3^4)² − (2^6)² We know that: x² - y² = (x + y)(x - y) So, we get: (3^4)² − (2^6)² = (3^4 + 2^6)(3^4 - 2^6) = (81 + 64)(81 - 64) = (145)(17) = (5)(29)(17) The greatest ...”
October 26, 2018
Brent@GMATPrepNow posted a reply to When Q is divided by W, the quotient is R and the remainder in the Problem Solving forum
“-----ASIDE----------------------- There''s a nice rule that says, "If N divided by D equals Q with remainder R, then N = DQ + R" For example, since 17 divided by 5 equals 3 with remainder 2, then we can write 17 = (5)(3) + 2 Likewise, since 53 divided by 10 equals 5 with remainder 3, ...”
October 26, 2018
Rich.C@EMPOWERgmat.com posted a reply to Cars J and K are making the trip from City A to City B. Car in the Problem Solving forum
“Hi All, We''re told that Cars J and K are making the trip from City A to City B. Car J departs from City A 15 minutes AFTER Car K does, both cars travel along the same route and Car K travels at a constant speed that is 80% the constant speed of Car J. We''re asked for the number of MINUTES that ...”
October 26, 2018
Rich.C@EMPOWERgmat.com posted a reply to Carmelo and LeBron participate in a seven-person footrace on in the Problem Solving forum
“Hi All, We''re told that Carmelo and LeBron participate in a seven-person footrace on the basketball court during All-Star Weekend, all seven contestants finish and there are no ties. We''re asked for the number of different arrangements in which Carmelo defeats LeBron. This question is a ...”
October 26, 2018
Rich.C@EMPOWERgmat.com posted a reply to What is the largest prime factor of the expression 3^8 − 2 in the Problem Solving forum
“Hi All, We''re asked to find the LARGEST prime factor of the expression 3^8 - 2^12. Certain Quant questions ultimately come down to ''rewriting'' information that you''ve been given. By rewriting 3^8 and 2^12 as "squared" terms, we''ll have a ''difference of squares'', which is a ...”
October 26, 2018
Rich.C@EMPOWERgmat.com posted a reply to GMAT Retake?? in the I just Beat The GMAT! forum
“Hi GMAT_quest92, To start, a 710/Q50 is an outstanding score (it''s right around the 90th percentile overall), so you can comfortably apply to any Business Schools that interest you. Your question - in the broader sense - is about AFTER Business School though - so you might not find the exact ...”
October 26, 2018
Brent@GMATPrepNow posted a reply to Tricky: If AB || DE, and AB = 10, what is the length of DE? in the Data Sufficiency forum
“Let''s first add the given information (and their implications) to the diagram If AB || DE, we know that ∠BAC = ∠CED and ∠ABC = ∠DCE Also, since vertically opposite angles are equal, we know that ∠ACB = ∠DCE https://i.imgur.com/fgDp7Yh.png Now that we''ve identified 3 pairs of ...”
October 26, 2018
Brent@GMATPrepNow posted a new topic called Tricky: If AB || DE, and AB = 10, what is the length of DE? in the Data Sufficiency forum
“https://i.imgur.com/jyTAK6n.png If AB || DE, and AB = 10, what is the length of DE? (1) BC = 6 and CE = 4 (2) DC = 3 and CB = 6 Answer: B Difficulty level: 650 – 700 Source: www.gmatprepnow.com”
October 25, 2018
Brent@GMATPrepNow posted a reply to If |x-6|=2x, then x=? in the Problem Solving forum
“There are 3 steps to solving equations involving ABSOLUTE VALUE: 1. Apply the rule that says: If |x| = k, then x = k or x = -k 2. Solve the resulting equations 3. Plug solutions into original equation to check for extraneous roots Step 1: x - 6 = 2x or x - 6 = -2x case a: x - 6 = 2x Step ...”
October 25, 2018
Rich.C@EMPOWERgmat.com posted a reply to GMAT with NO background in the GMAT Strategy forum
“Hi Rex, Studying for (and taking) the GMAT in the near-term - years before you might actually need it - is a really smart move. By focusing on the GMAT now, you can avoid the external pressure of a looming deadline and give yourself plenty of time to learn the content, patterns and little ...”
October 25, 2018
Rich.C@EMPOWERgmat.com posted a reply to Where is the registration offer?? in the Suggestions and Feedback forum
“Hi gmat800live, The current free Account that we offer through BeatTheGMAT is not for the full Course - it''s for some specific resources within the Course (including the Grammar Master Course). You can access the entire EMPOWERgmat Course for free through the free trial on our website though. ...”
October 25, 2018
Brent@GMATPrepNow posted a reply to CHALLENGE: 10 teams (A, B, C, D, E, F, G, H, I and J) partic in the Problem Solving forum
“First determine the TOTAL number of games played. We can select 2 teams from 10 teams in 10C2 ways (= 45 ways) So, there will be 45 games in TOTAL IMPORTANT: Each team plays 9 games For each game, 2 points are awarded. So, the TOTAL number of POINTS awarded = (2)(45) = 90 Teams A, B, C, ...”
October 24, 2018
Brent@GMATPrepNow posted a reply to Noelle walks from point A to point B at an average speed of in the Problem Solving forum
“For these kinds of questions, I typically follow the approach that Fabio used (assign a nice value to the distance). But we can also solve the question algebraically: Let d = the distance between Points A and B. Let x = the Noelle''s speed from Point B to Point A. We want the average ...”
October 24, 2018
Brent@GMATPrepNow posted a reply to What is the median number of employees assigned per project in the Data Sufficiency forum
“Target question: What is the median number of employees assigned per project? Statement 1: 25 percent of the projects at Company Z have 4 or more employees assigned to each project. Let''s pretend that there are 4 projects altogether. There are several sets of values that meet this condition. ...”
October 24, 2018
Rich.C@EMPOWERgmat.com posted a reply to In a certain company, the ratio of the number of manager to in the Problem Solving forum
“Hi swerve, We''re told that the ratio of the number of manager to the number of production-line workers is 5 to 72 - and IF 8 additional production-line workers were to be hired, then the ratio of the number of managers to the number of production-line workers would be 5 to 74. We''re asked for ...”
October 23, 2018
Rich.C@EMPOWERgmat.com posted a reply to GMAT with NO background in the GMAT Strategy forum
“Hi Rex, Since it sounds like you''re just beginning your studies, then it would be a good idea to take a FULL-LENGTH practice CAT Test; you can take 2 for free at www.mba.com (and they come with some additional practice materials). If you want to do a little studying first, so that you can ...”
October 23, 2018
Rich.C@EMPOWERgmat.com posted a reply to Which CATs should I buy? MGMAT/Kaplan/Veritas....etc in the GMAT Strategy forum
“Hi omkarnikte, The scoring algorithm on the Official GMAT is far more complicated than most people realize. Since that algorithm is proprietary, no GMAT company has an exact match for it, thus CAT scores can vary a bit based on the ''biases'' involved in their respective designs. The most ...”
October 23, 2018
Brent@GMATPrepNow posted a reply to In a certain company, the ratio of the number of manager to in the Problem Solving forum
“One option is to use TWO VARIABLES Let M = CURRENT # of managers Let W = CURRENT # of production-line workers The ratio of the number of managers to the number of production-line workers is 5 to 72. So, we can write: M/W = 5/72 Cross multiply to get: 5W = 72M If 8 additional ...”
October 23, 2018
Brent@GMATPrepNow posted a reply to When 100 is divided by positive integer x, the remainder is in the Problem Solving forum
“A fast approach is to find a value of x that meets the given condition: When 100 is divided by positive integer x, the remainder is 2 Well, x = 98 satisfies that condition, since 100 divided by 98 = 1 with remainder 2 What is the remainder when 198 is divided by x? Well, 198 divided by 98 ...”
October 23, 2018
Brent@GMATPrepNow posted a reply to Bite-sized video lessons from GMAT Prep Now in the GMAT Math forum
“Range and Standard Deviation Video: https://www.youtube.com/watch?v=FbAlIjw2fwY Cheers, Brent”
October 23, 2018
Brent@GMATPrepNow posted a reply to Which of the following values, when inserted into the set of in the Problem Solving forum
“Let''s test each answer choice.... A. 2 The new set becomes {2, 5, 10, 12, 13, 17, 22, 22} Since we have an EVEN number of values in the set, the median equals the average of the two middlemost numbers. So, median = (12 + 13)/2 = 25/2 = 12.5 No good - we want the median to be 15 B. ...”
October 23, 2018
Brent@GMATPrepNow posted a reply to What are the coordinates of point B in the figure above ? in the Data Sufficiency forum
“IMPORTANT: For geometry Data Sufficiency questions, we are typically checking to see whether the statements "lock" a particular angle, length, or shape into having just one possible measurement. This concept is discussed in much greater detail in the video below. Target question: What ...”
October 23, 2018
Brent@GMATPrepNow posted a reply to The range of set A is 24 and the range of set B is 20. What in the Problem Solving forum
“If the range of set A is 24, and we add more values (from set B) to set A, then the range of the resulting set must be greater than or equal to 24 (that is, the range of a set cannot get smaller upon adding MORE numbers to that set). For this reason, we can ELIMINATE answer choice A. From ...”
October 23, 2018
Brent@GMATPrepNow posted a reply to If x and y are positive integers, what is the remainder when in the Data Sufficiency forum
“ Given: x and y are positive integers Target question: What is the remainder when x^y is divided by 10? This is a good candidate for rephrasing the target question. Notice that 43 divided by 10 leaves remainder 3, and 127 divided by 10 leaves remainder 7, and 618 divided by 10 leaves ...”
October 23, 2018
Brent@GMATPrepNow posted a new topic called CHALLENGE: 10 teams (A, B, C, D, E, F, G, H, I and J) partic in the Problem Solving forum
“10 teams (A, B, C, D, E, F, G, H, I and J) participate in a soccer tournament in which each team plays every other team once. For each game played, points are awarded to the teams as follows: 0 points for losing the game 1 point each for tying the game 2 points for winning the game After ...”
October 22, 2018
Brent@GMATPrepNow posted a reply to Clarissa will create her summer reading list by randomly in the Problem Solving forum
“Take the task of creating the reading list and break it into stages. Stage 1: Select a book to read 1st There are 10 books to choose from. So, we can complete stage 1 in 10 ways Stage 2: Select a book to read 2nd There are 9 books remaining to choose from (since we already chose a book ...”
October 22, 2018
Brent@GMATPrepNow posted a reply to A jar contains only green pencils and red pencils. If the in the Data Sufficiency forum
“Target question: What percentage of the pencils are green? Given: The jar contains only green pencils and red pencils. Statement 1: The jar contains 75 red pencils. If 75 of the 225 pencils are red, then the remaining 150 pencils are GREEN. 150/225 = 2/3 = 66 2/3%, so the answer to ...”
October 22, 2018
Brent@GMATPrepNow posted a reply to Challenge Question: In the x-y coordinate plane, does line k in the Data Sufficiency forum
“Target question: Does line k have a positive x-intercept? Statement 1: (slope of line k)(y-intercept of line k) > 0 There are two possible cases that that satisfy statement 1: - the slope and y-intercept are both positive - the slope and y-intercept are both negative Let''s examine ...”
October 21, 2018
Brent@GMATPrepNow posted a reply to What is the area of the triangle formed by the intersection in the Problem Solving forum
“Here''s a similar question to practice with: https://www.beatthegmat.com/area-of-triangle-formed-by-intersections-of-3-lines-t276079.html Cheers, Brent”
October 21, 2018
Rich.C@EMPOWERgmat.com posted a reply to Brian purchased a bouquet of 40 flowers for his mother for in the Problem Solving forum
“Hi All, We''re told that Brian purchased a bouquet of 40 flowers for his mother for her birthday; roses cost $1.50 each and tulips cost$1.00 each , and he spent $48 in total buying only those two types of flowers. We''re asked for the number of tulips that he bought. This question can be solved ...” October 20, 2018 Rich.C@EMPOWERgmat.com posted a reply to At a constant speed of 72 kilometers per hour, a vehicle in the Problem Solving forum “Hi All, We''re told that a vehicles travels at a constant speed of 72 kilometers per HOUR. We''re asked what that speed is in kilometers per SECOND. This question is really just about ''unit conversions'', although at a certain point you can use the ''spread'' of the answer choices to your ...” October 20, 2018 Rich.C@EMPOWERgmat.com posted a reply to There are between 100 and 110 cards in a collection of cards in the Problem Solving forum “Hi swerve, We''re told that there are between 100 and 110 cards in a collection of cards. If the cards are counted out 3 at a time, then there are 2 left over, but if they are counted out 4 at a time, then there is 1 left over. We''re asked for the total number of cards in the collection. This ...” October 20, 2018 Rich.C@EMPOWERgmat.com posted a reply to Average of 4 practice test scores is 617; Can I cross 700? in the GMAT Strategy forum “Hi anmkgmat2018, GMAC has publicly stated that the Official Score that you earn on Test Day is within +/- 30 points of actual ability. Assuming a similar ''swing'' in how your CATs function, 3 of your last 4 CAT score results show that you essentially performed the same each time (about 600 +/- ...” October 20, 2018 Brent@GMATPrepNow posted a new topic called Challenge Question: In the x-y coordinate plane, does line k in the Data Sufficiency forum “In the x-y coordinate plane, does line k have a positive x-intercept? (1) (slope of line k)(y-intercept of line k) > 0 (2) (slope of line k) - (y-intercept of line k) < 0 Answer: A Difficulty level: 650 – 700 Source: www.gmatprepnow.com” October 19, 2018 Brent@GMATPrepNow posted a reply to When positive integer N is divided by positive integer J, in the Problem Solving forum “ASIDE: 7/2 = 3 1/2 = 3 + 0.5 = 3.5 Notice that 1 is the remainder when we divide 7 by 2. 23/5 = 4 3/5 = 4 + 0.6 = 4.6 Notice that 3 is the remainder when we divide 23 by 5. 31/4 = 7 3/4 = 7 + 0.75 = 7.75 Notice that 3 is the remainder when we divide 31 by 4. GIVEN: N/J = 134.08 This means ...” October 19, 2018 Brent@GMATPrepNow posted a reply to If there are more than two numbers in a certain list, is in the Data Sufficiency forum “[quote="Jay@ManhattanReview"] Hey Jay, I thought I should point out that case 2 doesn''t satisfy the statement. If we choose 1 and 2 from the set, then the product isn''t 0. That said, {0, 0, 0, 0, 1} meets the given condition, as does {0, 0, 0, 0, 0, 0, 0, 3} etc Cheers, ...” October 19, 2018 Brent@GMATPrepNow posted a reply to If -1<x<0, Which of the following is listed in ascendi in the Problem Solving forum “Let''s test a value of x. If -1 < x < 0, then x COULD equal -1/2 So, x^(-1) = (-1/2)^(-1) = 1/(-1/2) = -2 And, x^(-2) = (-1/2)^(-2) = 1/(-1/2)^2 = 1/(1/4) = 4 And, x^2 = (-1/2)^2 = 1/4 Listed in ascending order, we get: -2, 1/4, 4 In other words, x^(-1), x^2, x^(-2) Answer: A ...” October 19, 2018 Rich.C@EMPOWERgmat.com posted a reply to In a certain math department, students are required to in the Problem Solving forum “Hi All, This question can be solved by TESTing VALUES and taking the proper notes. We''re told that there are two classes (Calculus and Trigonometry) and each is offered in beginner and advanced courses - and that each student is enrolled in just one course. The number of students enrolled in ...” October 19, 2018 Rich.C@EMPOWERgmat.com posted a reply to The rear wheels of a car crossed a certain line 0.5 second in the Problem Solving forum “Hi All, Since this question is wordy and the answers are somewhat "crazy"-looking, it''s possible that you might feel overwhelmed by this prompt. If you stay calm though and do the unit conversions properly, then you can use the answer choices to your advantage (and eliminate most of ...” October 19, 2018 Rich.C@EMPOWERgmat.com posted a reply to When positive integer N is divided by positive integer J, in the Problem Solving forum “Hi All, This question is a ''lift'' of an Official Guide question: OG2018 and OG2019 pg. 170, question #154 We''re told that P and J are positive INTEGERS, when P is divided by J, the REMAINDER is 14 and N/J = 134.08. We''re asked for the value of J. This question has a great ''math ...” October 19, 2018 Rich.C@EMPOWERgmat.com posted a reply to cost of package in the Problem Solving forum “Hi All, We''re told that the cost of sending a package is T cents for the FIRST 1/4 kilogram and T/5 cents for EACH additional 1/4 kilogram or fraction thereof. We''re asked for the cost, in cents, to send a P kilogram package at this rate, where P is an integer greater than 1. This question can ...” October 19, 2018 Brent@GMATPrepNow posted a reply to The latest model of space shuttle can achieve a maximum in the Problem Solving forum “GIVEN: The shuttle can travel 25 miles in 1 second So, the shuttle can travel 1500 miles in 60 seconds In other words, the shuttle can travel 1500 miles in 1 MINUTE So, the shuttle can travel 90,000 miles in 60 MINUTES In other words, the shuttle can travel 90,000 miles in 1 HOUR In other ...” October 18, 2018 Brent@GMATPrepNow posted a reply to A jar contains 6 red marbles and 9 blue marbles. If Evelyn in the Problem Solving forum “P(both are same color) = P(1st marble is red AND 2nd marble is red OR 1st marble is blue AND 2nd marble is blue) = x P(2nd marble is red)] + x P(2nd marble is blue)] = x 5/14] + x 8/14] = x 5/14] + x 8/14] = 10/70 + 24/70 = 34/70 = 17/35 Answer: D Cheers, Brent” October 18, 2018 Brent@GMATPrepNow posted a reply to Bite-sized video lessons from GMAT Prep Now in the GMAT Math forum “Time management strategy for test day Video: https://www.youtube.com/watch?v=bWrUiBT83PQ Cheers, Brent” October 18, 2018 Brent@GMATPrepNow posted a reply to In the x-y coordinate plane, line k passes through in the Problem Solving forum “Notice that, if the line passes through the origin, then the line has slope -4/5 (aka a slope of -0.8), but the line will not have a negative x-intercept Notice that, if the line passes through the (0,4), then the line will have slope 0, BUT the line will not have a negative x-intercept. See ...” October 18, 2018 Brent@GMATPrepNow posted a reply to f[f{f(x)}]=??? in the GMAT Math forum “Useful property: 1/(a/b) = b/a We want: ff(5)}] = f1/6}] f{1/6} = 1/(1 + 1/6) = 1/(7/6) = 6/7 So, ff{1/6}] = f6/7] Finally, f[6/7] = 1/(1 + 6/7) = 1/(13/7) = 7/13 Answer: B (since 21/39 reduces to the equivalent fraction 7/13) Cheers, Brent” October 18, 2018 Brent@GMATPrepNow posted a reply to In the month of August, Pentheus Corporation made$200,000 in the Problem Solving forum
“In the month of August, Pentheus Corporation made $200,000 in profit. Pentheus made 6% of that profit on the second Wednesday of August. 1% of$200,000 = $2,000, so 6% of$200,000 = (6)($2,000) =$12,000 So, the profit on that day = $12,000 If the profits that day were approximately 14.5% of ...” October 18, 2018 Brent@GMATPrepNow posted a reply to Brian purchased a bouquet of 40 flowers for his mother for in the Problem Solving forum “We can solve this question using either 1 variable or 2 variables. Here''s an approach that involves 1 variable: Let t = # of tulips in bouquet So. 40 - t = # of roses in bouquet So, ($1.00)(t) = the total COST of all t tulips And ($1.50)(40 - t) = the total COST of all 40-t roses ...” October 18, 2018 Brent@GMATPrepNow posted a reply to In a town of 8,000 residents, 65 percent of all residents in the Problem Solving forum “Another approach is to use the Double Matrix Method. This technique can be used for most questions featuring a population in which each member has two characteristics associated with it (aka overlapping sets questions). Here, we have a population of residents, and the two characteristics are: ...” October 17, 2018 Rich.C@EMPOWERgmat.com posted a reply to An automobile manufacturer offers a station wagon with in the Problem Solving forum “Hi All, Sometimes Combination Formula questions come with answers that are relatively small. In this prompt, we know that there are at least 3 options, but no more than 8 options. In these situations, it''s usually pretty easy to "map out" all of the possible combinations, without ...” October 17, 2018 Rich.C@EMPOWERgmat.com posted a reply to Maria wants to send a package overseas. She can either pay in the Data Sufficiency forum “Hi All, We''re told that Maria wants to send a package overseas. She can either pay shipping company A an amount dependent on the DISTANCE of the delivery, or pay shipping company B an amount dependent on the WEIGHT of the package. We''re asked which option is less expensive. 1) Company A ...” October 17, 2018 Brent@GMATPrepNow posted a reply to What is the remainder if 7^10 is divided by 100? in the Problem Solving forum “Sweeeeeeeeeeeeet solution, Scott!! Cheers, Brent” October 17, 2018 Brent@GMATPrepNow posted a reply to If x, y, and z are all nonzero numbers, and x = y + z, which in the Problem Solving forum “NOTE: this is one of those questions that require us to check/test each answer choice. In these situations, always check the answer choices from E to A, because the correct answer is typically closer to the bottom than to the top. For more on this strategy, see my article: ...” October 16, 2018 Brent@GMATPrepNow posted a reply to Set X consists of different positive numbers arranged in in the Data Sufficiency forum “Target question: What is the arithmetic mean of set X? Given: Set X consists of different positive numbers arranged in ascending order: K, L, M, 5, 7. K, L and M are consecutive integers This means that EITHER K, L, M = 1, 2, 3 respectively, OR K, L, M = 2, 3, 4 respectively Head straight ...” October 16, 2018 Brent@GMATPrepNow posted a reply to A Martian bat flies at 60 yards per second from its nest to in the Problem Solving forum “Rich''s approach is definitely the best (i.e., fastest) way to solve this question. However, if the answer choices weren''t so sweet, here''s an algebraic solution Average speed = (total distance traveled)/(total travel time) Let''s assign nice values to the distances. These values should ...” October 16, 2018 Brent@GMATPrepNow posted a reply to Charlie takes 2.5 hours to fly from Los Angeles to Mexico in the Problem Solving forum “Average speed = (total distance traveled)/(total travel time) So, Average speed = 1200/2.5 = 2400/5 = 4800/10 = 480 mph Answer: D Cheers, Brent” October 16, 2018 Brent@GMATPrepNow posted a reply to A certain NYC taxi driver has decided to start charging a in the Problem Solving forum “Here''s an algebraic approach: A certain taxi driver charges a rate of r CENTS per person per mile r CENTS = r/100 DOLLARS Since there are 3 people, the rate is (3)(r/100) DOLLARS per mile In other words, the rate is 3r/100 dollars per mile. With a 50% discount, the new rate = ...” October 16, 2018 Brent@GMATPrepNow posted a new topic called In the x-y coordinate plane, line k passes through in the Problem Solving forum “In the x-y coordinate plane, line k passes through the point (5, -4) and has a negative x-intercept. Which of the following COULD be the equation of line k? i) y = -0.4x - 2 ii) y = 2 - 1.2x iii) y = -0.7x - 1.5 A) i only B) ii only C) iii only D) i & ii only E) i & iii only ...” October 16, 2018 Rich.C@EMPOWERgmat.com posted a reply to A rectangular garden is to be twice as long as it is wide. in the Problem Solving forum “Hi All, We''re told that a rectangular garden is to be TWICE as long as it is wide and 360 total yards of fencing, including the gate, will completely enclose the garden. We''re asked for the length of the garden, in yards. This question can be solved in a couple of different ways, including by ...” October 16, 2018 Rich.C@EMPOWERgmat.com posted a reply to A Martian bat flies at 60 yards per second from its nest to in the Problem Solving forum “Hi All, We''re told that a Martian bat flies at 60 yards per second from its nest to a dry lake. When it arrives there, it immediately continues at 45 yards per second to a nearby cave. If the distance between the lake and the cave is HALF the distance between the nest and the lake, we''re asked ...” October 16, 2018 Rich.C@EMPOWERgmat.com posted a reply to Charlie takes 2.5 hours to fly from Los Angeles to Mexico in the Problem Solving forum “Hi All, We''re told that Charlie takes 2.5 hours to fly from Los Angeles to Mexico City, which is a total distance of 1200 miles. We''re asked for the average speed of his plane in miles per hour. This is a straight-forward ''Average Speed'' question, so we can just plug in the numbers at get ...” October 16, 2018 Rich.C@EMPOWERgmat.com posted a reply to Anna and Carol buy CDs and tapes at a music store that sells in the Problem Solving forum “Hi All, We''re told that Anna and Carol buy CDs and tapes at a music store that sells each of its CDs for a certain price and each of its tapes for a certain price. Anna spends TWICE as much as Carol spends, buying THREE times as many CDs and the SAME number of tapes. If Carol spends$50.00 on ...”
October 16, 2018
Brent@GMATPrepNow posted a reply to Lindsay can paint 1/x of a certain room in one hour. If in the Problem Solving forum
“This appears to be a slightly different version of this official question: https://www.beatthegmat.com/work-rate-problem-5-t292679.html HOWEVER, unless I''m missing something, the correct answer is missing. Cheers, Brent”
October 15, 2018
Brent@GMATPrepNow posted a reply to How many factors does the number X have? in the Data Sufficiency forum
“Target question: How many factors does the number X have? Statement 1: X is divisible by 47 Let''s TEST some values. There are several values of X that satisfy statement 1. Here are two: Case a: X = 47. The factors of 47 are {1, 47}. So, the answer to the target question is X has 2 ...”
October 15, 2018
Brent@GMATPrepNow posted a reply to A rectangular solid S, has dimensions 4 by 9 by k. What is in the Data Sufficiency forum
“Target question: What is the value of k? Given: A rectangular solid S, has dimensions 4 by 9 by k Statement 1: 4 < k < 9 Since k can have ANY value between 4 and 9, statement 1 is NOT SUFFICIENT Statement 2: A cube of side 6 has the same volume as rectangular solid S. So ...”
October 15, 2018
Brent@GMATPrepNow posted a reply to In the rectangular coordinate system above, if the in the Data Sufficiency forum
“I think that, if this were an official GMAT question, the correct answer would be E (not B), because we aren''t specifically told that the dotted lines are parallel to the x-axis and the y-axis. If those dotted lines aren''t parallel to those axes, the we can''t determine the value of y. ...”
October 15, 2018
Brent@GMATPrepNow posted a reply to In the figure above, triangle ABC is equilateral, and point in the Problem Solving forum
“It may help to add some lines to the diagram. First add lines from the center to the 3 vertices. https://s8.postimg.cc/e412m8uq9/clk1.jpg Aside, we know that each angle is 120º since all three (equivalent) angles must add to 360.º Then draw a circle so that the triangles vertices are on ...”
October 15, 2018
Brent@GMATPrepNow posted a reply to The mass of 1 cubic meter of a substance is 800 kg under in the Problem Solving forum
“GIVEN: 1 cubic METER of the substance weighs 800 KILOGRAMS 1 kg =1,000 grams, so we can write: 1 cubic METER of the substance weighs 800,000 GRAMS 1 cubic meter = 1,000,000, so we can write: 1,000,000 cubic CENTIMETERS of the substance weighs 800,000 GRAMS What is the volume in cubic ...”
October 14, 2018
Brent@GMATPrepNow posted a reply to At a family summer party, each of the x members of the in the Problem Solving forum
“These kinds of questions (Variables in the Answer Choices - VIACs) can be answered algebraically or using the INPUT-OUTPUT approach. The Ash Mo solved the question algebraically, so let''s use the INPUT-OUTPUT approach. It might be useful to choose a number that works well with the fractions ...”
October 13, 2018
Brent@GMATPrepNow posted a reply to When A and B are positive integers, is AB a multiple of 4? in the Data Sufficiency forum
“Target question: Is AB a multiple of 4? Useful property: If N is divisible by d, we can say that N = dk for some integer k For example, if N is divisible by 5, we can say that N = 5k for some integer k Statement 1: The greatest common divisor of A and B is 6 This means that A is divisible ...”
October 13, 2018
Brent@GMATPrepNow posted a reply to How much time did it take a certain car to travel 400 in the Data Sufficiency forum
“Target question: How long did it take to travel 400km To find the travel time, we need to know the average speed traveled. Let x = the average speed traveled. REPHRASED target question: What is the value of x? Statement 1: The car traveled the first 200 km in 2.5 hrs No info about the ...”
October 13, 2018
Brent@GMATPrepNow posted a reply to Challenge question: What is the sum of all in the Problem Solving forum
“Approach #1 If we recognize that x^(2/3) = u-substitution. Let u = x^(1/3) Now take original equation and replace x^(1/3) with u to get: u² - u - 2 = 4 Subtract 4 from both sides to get: to get: u² - u - 6 = 0 Factor: (u - 3)(u + 2) = 0 So, the two solutions here are u = 3 and u = -2 ...”
October 13, 2018
Brent@GMATPrepNow posted a reply to A certain club has 10 members, including Harry. One of the 1 in the Problem Solving forum
“As with many probability questions, we can solve this using counting techniques or probability rules. So, before you embark on one approach, try to determine which one is faster. Here''s the probability approach: P(Harry selected Secretary or Treasurer) = 1 - P(Harry selected president OR ...”
October 13, 2018
Rich.C@EMPOWERgmat.com posted a reply to The probability of winning game A is X and the probability in the Problem Solving forum
“Hi All, We''re told that the probability of winning Game A is X and the probability of winning Game B is Y. We''re asked when playing a SINGLE round of EACH of the two games, what is the probability of winning EXACTLY ONCE. This question can be solved in a couple of different ways, including by ...”
October 13, 2018
Rich.C@EMPOWERgmat.com posted a reply to During 2005, a company produced an average of 2,000 products in the Problem Solving forum
“Hi Swerve, Although the prompt does not explicitly state it, we''re meant to infer that the company continues to produce products EVERY month (in the years 2005 through 2008, inclusive). A 200% increase in the monthly average (from 2005) would be 6,000 products per month for the ENTIRE 4-YEAR ...”
October 13, 2018
Rich.C@EMPOWERgmat.com posted a reply to Probability in the Problem Solving forum
“Hi yoshi97, When posting a GMAT questions, you should make sure to post the 5 answer choices (as sometimes the answers provide a clue as to how to approach the question in the most efficient way possible or a shortcut to avoiding a math-heavy approach). Here we''re told that of all of the ...”
October 13, 2018
Rich.C@EMPOWERgmat.com posted a reply to Full time student in the GMAT Strategy forum
“Hi Purvee, Raising a 490 to a 700+ will likely require at least another 3 months of consistent, guided study, even if you are studying full time - and you''ll have to make significant improvements to how you handle BOTH the Quant and Verbal sections. Thankfully, the GMAT is a consistent, ...”
October 12, 2018
Brent@GMATPrepNow posted a reply to The average age of a group of n people is 15 yrs. One more in the Problem Solving forum
“The average age of a group of n people is 15 yrs. So, (sum of all n ages)/n = 15 Multiply both sides by n to get: (sum of all n ages) = 15n One more person aged 39 joins the group and the new average is 17 yrs. IMPORTANT: Once this 39-year-old is added to the group, the (NEW sum of ages) = ...”
October 12, 2018
Brent@GMATPrepNow posted a new topic called Challenge question: What is the sum of all in the Problem Solving forum
“What is the sum of all solutions to the equation x^(2/3) - x^(1/3) - 2 = 4? A) -35 B) -19 C) 7 D) 19 E) 35 Answer: D Source: www.gmatprepnow.com Difficulty level: 600 - 650”
October 12, 2018
Brent@GMATPrepNow posted a reply to Challenge question: j and k are positive integers in the Data Sufficiency forum
“ Given: n = 10^j + k Target question: Is n divisible by 15? Key concepts: - If n is divisible by 15, then n must be divisible by 3 AND by 5 - If n is divisible by 3, then the sum of n''s digits must be divisible by 3 (for example, we know that 747 is divisible by 3, because 7+4+7 = 18, ...”
October 12, 2018
Brent@GMATPrepNow posted a reply to Bite-sized video lessons from GMAT Prep Now in the GMAT Math forum
“Here''s our video on "if" versus "whether" https://www.youtube.com/watch?v=F2ZHtB088us Cheers, Brent”
October 11, 2018
Brent@GMATPrepNow posted a new topic called Challenge question: j and k are positive integers in the Data Sufficiency forum
“j and k are positive integers, and n = 10^j + k. Is n divisible by 15? (1) j and k are each divisible by 3 (2) j and k are each divisible by 5 Answer: A Difficulty level: 700+ Source: www.gmatprepnow.com”
October 11, 2018
Brent@GMATPrepNow posted a reply to Julie opened a lemonade stand and sold lemonade in two in the Data Sufficiency forum
“This question illustrates a common trap on the GMAT. For statement 2, we''re able to write the equation 52x + 58y = 492 , and in high school we learned that, if we''re given 1 equation with 2 variables, we cannot find the value of either variable. However, if we restrict the variables to ...”
October 11, 2018
Rich.C@EMPOWERgmat.com posted a reply to Full time student in the GMAT Strategy forum
“Hi Purvee, To start, many Test Takers spend 3 months (or more) of consistent study time before they hit their ''peak'' scores, so if you limit your timeframe to just 2 months, then there might be a limit to how much you can improve. Before I can offer you the specific advice that you’re ...”
October 10, 2018
Rich.C@EMPOWERgmat.com posted a reply to Dick and Jane each saved $3000 in 1989. In 1990 Dick save 8 in the Problem Solving forum “Hi All, We''re told that Dick and Jane EACH saved$3,000 in 1989. In 1990, Dick saved 8 percent MORE than he did in 1989, and TOGETHER he and Jane saved a total of $5,000. We''re asked APPROXIMATELY what percent less did Jane save in 1990 than in 1989. This question essentially comes down to the ...” October 10, 2018 Rich.C@EMPOWERgmat.com posted a reply to Angela’s grade was in the 90th percentile out of 80 grades in the Problem Solving forum “Hi swerve, We''re told that Angela’s grade was in the 90th percentile out of 80 grades in her class and in another class of 100 students there were 19 grades higher than Angela’s grade. We''re asked - if nobody had the same grade as Angela’s grade, what percentile was Angela in the two ...” October 10, 2018 Rich.C@EMPOWERgmat.com posted a reply to Quant Question from Princeton Mock: in the GMAT Math forum “Hi Mrrinali, To start, you would likely receive more of a response if you posted your questions in the specific forum for that category. For example, the DS forum is here: https://www.beatthegmat.com/data-sufficiency-f7.html We''re told that Byrne and some of his friends (men and women) go ...” October 10, 2018 Brent@GMATPrepNow posted a reply to There are 5 cars to be displayed in 5 parking spaces with in the Problem Solving forum “Let R, R, R, B, Y represent the cars (by their colors) Notice that the three R''s are identical. So, the question becomes In how many different ways can we arrange the letters R, R, R, B and Y? ----------------ASIDE------------------------------ When we want to arrange a group of items in ...” October 10, 2018 Brent@GMATPrepNow posted a reply to Is x/11 an integer? in the Data Sufficiency forum “Target question: Is x/11 an integer? Statement 1: 5x/11 is an integer Let''s TEST some values There are several values of x that satisfy statement 1. Here are two: Case a: x = 11. Notice that 5x/11 = 5(11)/11 = 5, which is an integer. In this case, x/11 = 11/11 = 1. So, the answer to the ...” October 10, 2018 Brent@GMATPrepNow posted a reply to Dick and Jane each saved$3000 in 1989. In 1990 Dick save 8 in the Problem Solving forum
“Here''s the original wording: In 1990, Dick saved 8 percent more than in 1989 So, Dick''s savings in 1990 = 1.08($3000) =$3240 In 1990, Dick and Jane saved a total of $5,000. So, Jane''s savings =$5,000 - $3240 =$1760 Approximately what percent less did Jane save in 1990 than in ...”
October 10, 2018
Brent@GMATPrepNow posted a reply to Pam and Sue drove in the same car to a business meeting that in the Problem Solving forum
“Travel time = distance/speed Pam''s travel time = 120 miles/60 mph =2 hours Sue''s travel time = 120 miles/50 mph =2.4 hours Time difference = 2.4 hours - 2 hours = 0.4 hours To convert 0.4 hours to minutes, recognize that 1 hour = 60 minutes So, 0.4 hours = (0.4)(60) minutes = 24 minutes ...”
October 10, 2018
Rich.C@EMPOWERgmat.com posted a reply to Bob is training for a fitness competition. In order to in the Problem Solving forum
“Hi All, We''re told that Bob is training for a fitness competition. In order to increase his maximum number of pull-ups, he follows the following routine: he begins with 25 pull-ups, rests for thirty seconds, and then does 24 pull-ups and rests, dropping one pull-up each time (25, 24, 23, etc.) ...”
October 10, 2018
Rich.C@EMPOWERgmat.com posted a reply to A certain car traveled twice as many miles from Town A to in the Problem Solving forum
“Hi All, We''re told that a certain car traveled TWICE as many miles from Town A to Town B as it did from Town B to Town C. From Town A to Town B, the car averaged 12 miles per gallon, and from Town B to Town C, the car averaged 18 miles per gallon. We''re asked for the average MILES PER GALLON ...”
October 10, 2018
Rich.C@EMPOWERgmat.com posted a reply to If Jim drives k miles in 50 minutes, how many minutes will in the Problem Solving forum
“Hi All, We''re told that Jim drives K miles in 50 MINUTES. We''re asked how many MINUTES it will take him to drive 10 miles at the same rate. This question can be solved rather easily by TESTing VALUES. Since K can be any positive value, we can set K = 10. Thus, we know that Jim drives 10 ...”
October 10, 2018
Rich.C@EMPOWERgmat.com posted a reply to If P is an odd integer and (P^2 + Q * R) is an even integer, in the Problem Solving forum
“Hi All, We''re told that If P is an ODD integer and (P^2 + Q * R) is an EVEN integer. We''re asked which of the following MUST be true. This question can be solved with a mix of Number Properties and TESTing VALUES. To start, since P is ODD, we know that P^2 will also be ODD (since ODD^2 = ...”
October 10, 2018
Brent@GMATPrepNow posted a reply to A group of medical interns at Bohemus Medical School want to in the Problem Solving forum
“Take the task of arranging dates and break it into stages. Let A, B, C, D and E represent the 5 girls Stage 1: Select a boy to date girl A We can choose any of the 5 boys, so we can complete stage 1 in 5 ways Stage 2: Select a boy to date girl B Since we already selected a boy in ...”
October 9, 2018
Brent@GMATPrepNow posted a reply to A school library contains 200 hardcover and 300 paperback in the Problem Solving forum
“Another approach is to use the Double Matrix Method. This technique can be used for most questions featuring a population in which each member has two characteristics associated with it (aka overlapping sets questions). Here, we have a population of books, and the two characteristics are: - ...”
October 9, 2018
Brent@GMATPrepNow posted a reply to Bite-sized video lessons from GMAT Prep Now in the GMAT Math forum
“Here''s our video on the Double Matrix Method for overlapping sets: https://www.youtube.com/watch?v=jK-tiBrrf04 Cheers, Brent”
October 9, 2018
Brent@GMATPrepNow posted a reply to If x, y, and z are positive numbers, Is z between x and y? in the Data Sufficiency forum
“Target question: Is z between x and y? Statement 1: x < 2z < y There are several sets of values of x, y and z that satisfy this condition. Here are two: Case a: x = 3, y = 10, and z = 2, in which case z is NOT between x and y Case b: x = 1, y = 10, and z = 3, in which case z IS ...”
October 9, 2018
Brent@GMATPrepNow posted a reply to If the product of X and Y is a positive number, is the sum in the Data Sufficiency forum
“IMPORTANT CONCEPTS: An ODD power preserves the sign of the base. For example, (-5)^3 = -125 and 2^5 = 32 An EVEN power always yields a positive number (as long as the base ≠ 0 For example, (-5)^4 = 625 and 2^6 = 64 Target question: Is the sum of x and y negative? Given: the ...”
October 9, 2018
Brent@GMATPrepNow posted a reply to DS: Difficulty level: 700, Source: Economist in the GMAT Math forum
“The key word here is must So, if we can find a case in which an answer choice is NOT true, then we can eliminate that answer choice. A. x is odd and y is even. x = 3 and y = 11 satisfies the condition that x/y is not an integer Since y is NOT even, we can ELIMINATE A B. x is odd and y is ...”
October 9, 2018
Brent@GMATPrepNow posted a reply to James invested $5000 in scheme A for 1 year at a simple in the Problem Solving forum “Scheme A Interest = 5% of$5,000 = $250 Scheme B 10% interest compounded semi-annually means that the interest is compounded 2 times (in 1 year) at a rate of 5% each time One option is to apply the compound interest formula, but since we''re only compounding the interest twice, it may be ...” October 9, 2018 Rich.C@EMPOWERgmat.com posted a reply to Alex and Brenda both stand at point X. Alex begins to walk in the Problem Solving forum “Hi All, We''re told that Alex and Brenda both stand at point X, Alex begins to walk away from Brenda in a straight line at a rate of 4 miles per hour - and ONE HOUR later, Brenda begins to ride a bicycle in a straight line in the opposite direction at a rate of R miles per hour. We''re asked, if ...” October 9, 2018 Rich.C@EMPOWERgmat.com posted a reply to A farm used two harvesting machines, H and K, to harvest 100 in the Problem Solving forum “Hi All, We''re told that a farm used two harvesting Machines, H and K, to harvest 100 acres of wheat. Harvesting Machine H, working alone at its constant rate, harvested 40 acres of wheat in 8 hours. Then harvesting Machine K was brought in, and harvesting Machines H and K, working together at ...” October 9, 2018 Rich.C@EMPOWERgmat.com posted a reply to A retailer buys cases of 24 shirts for$30/case and then in the Problem Solving forum
“Hi All, We''re told that a retailer buys cases of 24 shirts for $30/case and then resells them in packs of 5 for$8/pack, the retailer sold ALL of the shirts it purchased and profited $84 on the sale. We''re asked for the number of PACKS of shirts that it sold. This question can be approached in ...” October 9, 2018 Rich.C@EMPOWERgmat.com posted a reply to 5 times n is three less than twice n. What number is three in the Problem Solving forum “Hi All, We''re told that 5 times N is three less than twice N. We''re asked to find the number that is three less than twice N. This question is essentially about ''translating'' sentences into equations and a bit of Algebra. "5 times N is three less than twice N"... 5(N) = 2(N) ...” October 9, 2018 Rich.C@EMPOWERgmat.com posted a reply to What is the probability of getting exactly three heads on in the Problem Solving forum “Hi All, We''re asked for the probability of getting EXACTLY three heads on five flips of a fair coin. This question can be approached in a couple of different ways, but they all involve a bit of ''Probability math.'' To start, since each coin has two possible outcomes, there are ...” October 9, 2018 Brent@GMATPrepNow posted a reply to A retailer buys cases of 24 shirts for$30/case and then in the Problem Solving forum
“The key information here is that the retailer sold all the shirts it purchased This is a huge hint! For example, we know that the retailer did NOT buy only 1 case of 24 shirts, because 24 shirts will not divide into packs of 5 shirts. Likewise, we know that the retailer did NOT buy 2 cases of ...”
October 8, 2018
Brent@GMATPrepNow posted a reply to If x^2-3x=10, what is the value of x? in the Data Sufficiency forum
“ Given: x² - 3x = 10 Subtract 10 from both sides to get: x² - 3x - 10 = 0 Factor: (x - 5)(x + 2) = 0 So, EITHER x = 5 OR x = -2 Target question: What is the value of x? Statement 1: x² - 4 = 0 Factor: (x + 2)(x - 2) = 0 So, EITHER x = -2 OR x = 2 When we combine this with the fact ...”
October 8, 2018
Brent@GMATPrepNow posted a reply to What is the greatest prime factor of 1+2+3+….+36? in the Problem Solving forum
“Useful formula: 1 + 2 + 3 + 4 + . . . . + n = (n)(n + 1)/2 So, 1 + 2 + 3 + …. + 36 = (36)(36 + 1)/2 = (36)(37)/2 = (18)(37) = (2)(3)(3)(17) So, the greatest prime factor is 37 Answer: E Cheers, Brent”
October 8, 2018
Rich.C@EMPOWERgmat.com posted a reply to Problem solving: Difficulty level: 700, Source: Jamboree in the Problem Solving forum
“Hi aishwaryav12, We''re told that X is an integer. We''re asked for the number of possible solutions for the equation X^2+5|X|+6=0. This question can approached in a couple of different ways, but you can actually solve it with Number Properties and avoid doing any calculations whatsoever. ...”
October 7, 2018
Rich.C@EMPOWERgmat.com posted a reply to A certain scholarship committee awarded scholarships in the in the Problem Solving forum
“Hi All, We''re told that a certain scholarship committee awarded scholarships in the amounts of $1250,$2500 and $4000 - there are twice as many$2500 scholarships as $4000 and it awarded three times as many$1250 scholarships as $2500 scholarships. A total of$37500 was awarded in $1250 ...” October 7, 2018 Rich.C@EMPOWERgmat.com posted a reply to Working alone, pump A can empty a pool in 3 hours. Working in the Problem Solving forum “Hi All, We''re told that working alone, Pump A can empty a pool in 3 HOURS and Pump B can empty the same pool in 2 HOURS. We''re asked how many MINUTES it would take the two pumps, working together, to empty the pool. This question can be solved in a couple of different ways, including with the ...” October 7, 2018 Brent@GMATPrepNow posted a reply to Bite-sized video lessons from GMAT Prep Now in the GMAT Math forum “In this short (3:25) video, we''ll examine the age-old question When do I use IF and when do we use WHETHER? Video link: https://www.youtube.com/watch?v=F2ZHtB088us Cheers, Brent” October 7, 2018 Brent@GMATPrepNow posted a reply to All assets in Karina's investment portfolio are divided in the Problem Solving forum “Let''s say Karina''s entire portfolio is worth$100 altogether. So, we want to divide this $100 into four integer amounts: w, x, y, z, where w < x < y < z, and we want to minimize the value of z In order to MINIMIZE the value of the z, we must MAXIMIZE the values of w, x, and y. Now ...” October 7, 2018 Brent@GMATPrepNow posted a reply to Beth and Jim each received a salary increase. If Jim's in the Data Sufficiency forum “Target question: Did Beth receive a greater dollar increase in salary than Jim? Given: Jim''s salary was increased by the same percent as Beth''s salary Statement 1: Before the increases, Jim''s salary was greater than$25,000. Since we have no information about Beth, there''s no way to ...”
October 7, 2018
Brent@GMATPrepNow posted a reply to Problem solving: Difficulty level: 700, Source: Jamboree in the Problem Solving forum
“Take: x² + 5|x| + 6 = 0 Subtract 6 from both sides to get: x² + 5|x| = -6 KEY CONCEPT: x² ≥ 0 and |x| ≥ 0 for all values of x In other words, x² will always be greater than or equal to 0 And |x| will always be greater than or equal to 0, which means 5|x| will always be greater than or ...”
October 7, 2018
Brent@GMATPrepNow posted a reply to TRICKY! There are n teams playing in a basketball tournam in the Problem Solving forum
“Good catch regor60! A few people alerted me to this error earlier in the day, but I was on the road and couldn''t respond. Man, I must have solved the question 3 or 4 times to make sure the numbers added up, BUT I never considered the impossibility of more than one team winning every game. ...”
October 7, 2018
Rich.C@EMPOWERgmat.com posted a reply to John tossed a fair coin 3 times. What is the probability in the Problem Solving forum
“Hi All, We''re told that John tossed a fair coin 3 times. We''re asked for the probability that the outcome was "tails" EXACTLY twice. This question can be approached in a number of different ways; sometimes the fastest way to answer these types of Probability questions is to just ...”
October 6, 2018
Brent@GMATPrepNow posted a reply to Is -3*x^3 <= -3? in the Data Sufficiency forum
“Target question: Is (-3)(x³) ≤ -3? This is a good candidate for rephrasing the target question. Take: (-3)(x³) ≤ -3? Divide both sides by -3 to get: x³ ≥ 1 Under what circumstance will x³ be greater than or equal to 1? Well, x³ EQUALS 1 when x = 1 So, x³ will be greater than ...”
October 6, 2018
Brent@GMATPrepNow posted a reply to If x + 5 > 2 and x - 3 < 7, the value of x must be bet in the Problem Solving forum
“GIVEN: x + 5 > 2 Subtract 5 from both sides of the inequality to get: x > -3 Or we can write this as -3 < x GIVEN: x - 3 < 7 Add 3 to both sides of the inequality to get: x < 10 COMBINE the inequalities to get: -3 < x < 10 Answer: A Cheers, Brent”
October 6, 2018
Brent@GMATPrepNow posted a reply to Each year for 4 years, a farmer increased the number of in the Problem Solving forum
“Here''s another approach: First notice that, if the number of trees increases by 1/4, then the new number is 5/4 times the original number. Let x = the # of trees in the orchard at the beginning of the 4 year period. (5/4)x = # of trees after 1 year (5/4)(5/4)x = # of trees after 2 years ...”
October 5, 2018
Brent@GMATPrepNow posted a reply to Health insurance Plan A requires the insured to pay $1000 or in the Problem Solving forum “Here''s an algebraic approach: Let T = TOTAL COST Plan A: Person pays EITHER$1000 OR 0.5T, whichever is LESS Plan B: Person pays $300 plus 20% of anything over$300. In other words, the person pays $300 + 0.2(T - 300) Since Plan A has two different scenarios, we need to test both. That ...” October 5, 2018 Rich.C@EMPOWERgmat.com posted a reply to Health insurance Plan A requires the insured to pay$1000 or in the Problem Solving forum
“Hi All, We''re told that Health insurance Plan A requires the insured to pay $1000 or 50% of total cost, whichever is LOWER. Plan B requires the insured to pay the initial$300, but IT then pays 80% of the cost over $300. We''re asked which of the following is a cost level for which both ...” October 5, 2018 Rich.C@EMPOWERgmat.com posted a reply to Which of the following is closest to the value of in the Problem Solving forum “Hi All, We''re asked which of the following numbers is closest to the value of the given fraction. While it might appear that some of the answers are ''close'' to one another, the reality is that each answer is 10 TIMES greater than the answer immediately below it - meaning that we can use ...” October 5, 2018 Rich.C@EMPOWERgmat.com posted a reply to Greg is training for a marathon by running to and from work in the Problem Solving forum “Hi All, We''re told that Greg is training for a marathon by running to and from work each day, a distance of 12 miles each way; he runs from home to work at an average speed of 6 miles per hour and returns at an average speed of 4 miles per hour. We''re asked for Greg’s average speed, in miles ...” October 5, 2018 Rich.C@EMPOWERgmat.com posted a reply to Vivian drives to her sister's house and back. She takes the in the Problem Solving forum “Hi All, We''re told that Vivian drives to her sister''s house and back. She takes the exact same route both ways; on the trip out she drives an average speed of 50 miles per hour and on the trip back she drives an average speed of 70 miles per hour. We''re asked for her approximate average speed ...” October 5, 2018 Rich.C@EMPOWERgmat.com posted a reply to Andrew bought pizzas for his swim team. Pepperoni pizzas in the Problem Solving forum “Hi All, We''re told that Andrew bought pizzas for his swim team; pepperoni pizzas cost$13 each, combination pizzas cost $17 each and he bought only pepperoni or combination pizzas (spending a total of$184 on pizzas). We''re asked for the TOTAL number of pizzas he bought. This question can be ...”
October 5, 2018
Brent@GMATPrepNow posted a new topic called Bite-sized video lessons from GMAT Prep Now in the GMAT Math forum
“I thought I''d start a thread featuring some of the videos from our course. This first video is one of my favorites. It covers a useful mental-math technique called Multiplying by Doubling and Halving (length 3:25) Video link: https://www.youtube.com/watch?v=D__dWwmgq2w All the best on ...”
October 5, 2018
Brent@GMATPrepNow posted a new topic called TRICKY! There are n teams playing in a basketball tournam in the Problem Solving forum
“Several teams are competing in a basketball tournament, and each team plays every other team once. Each game has exactly 1 winner and 1 loser (no ties). If 4 teams lost exactly 5 games, 5 teams won exactly 3 games, and each of the remaining teams won all of its games, what is the total number of ...”
October 5, 2018
Brent@GMATPrepNow posted a reply to Andrew bought pizzas for his swim team. Pepperoni pizzas in the Problem Solving forum
“This question illustrates the difference between the abstract math and real world math. From the given information, we''re able to create ONE equation: 13p + 17c = 184 In high school, we learned that, if we''re given 1 equation with 2 variables, we cannot find the value of either variable, so ...”
October 5, 2018
Brent@GMATPrepNow posted a reply to ||2-3|-|2-5||=? in the Problem Solving forum
“||2-3|-|2-5|| = ||-1|-|-3|| = |1-3|| = |-2| = 2 Answer: B Cheers, Brent”
October 5, 2018
Brent@GMATPrepNow posted a reply to What is the perimeter of quadrilateral Q? in the Data Sufficiency forum
“Target question: What is the perimeter of quadrilateral Q? If we recognize that each statement alone is not sufficient, we can jump straight to...... Statements 1 and 2 combined There are several quadrilaterals that satisfy BOTH statements. Here are two: Case a: rectangle Q has ...”
October 5, 2018
Rich.C@EMPOWERgmat.com posted a reply to If 5 people, each working at a constant rate can wash 8 cars in the Problem Solving forum
“Hi All, We''re told that 5 people, each working at a constant rate, can wash 8 cars in 40 MINUTES. We''re asked how many people working at that same constant rate are needed to wash A cars in B HOURS. With these types of questions, it often helps to determine the total amount of work needed to ...”
October 5, 2018
Rich.C@EMPOWERgmat.com posted a reply to Barbara invests $2400 in the National Bank at 5%. How much in the Problem Solving forum “Hi All, We''re told that Barbara invests$2400 in the National Bank at 5%. We''re asked how much additional money she must invest at 8% so that the TOTAL annual income will be equal to 6% of her TOTAL investment. This question can be solved in a couple of different ways, including by TESTing THE ...”
October 5, 2018
Rich.C@EMPOWERgmat.com posted a reply to The juice stall at the circus stocked just 2 brands of in the Problem Solving forum
“Hi All, You might recognize this as a ''lift'' of an Official Guide question. You can find that question - and a discussion of how to solve it - here: https://www.beatthegmat.com/what-mistake-am-i-making-in-this-substitution-last-sunday-a-t276293.html GMAT assassins aren''t born, they''re ...”
October 4, 2018
Brent@GMATPrepNow posted a reply to A car salesman earns a base salary of $1,000 per month plus in the Problem Solving forum “Let x = number of cars sold in 1 month So, his pay =$1000 + ($200)(n) If he earned$2,200 in February, how many cars does he have to sell in March in order to double his February earnings? If we double $2,200, we get$4,400 We need: $1,000 + ($200)(n) = $4400 Subtract$1,000 from both sides ...”
October 4, 2018
Rich.C@EMPOWERgmat.com posted a reply to A car salesman earns a base salary of $1,000 per month plus in the Problem Solving forum “Hi All, We''re told that a car salesman earns a base salary of$1,000 per month plus a commission of $200 for each car he sells. He earned$2,200 in February. We''re asked for the number of cars he would have to sell in March in order to DOUBLE his February earnings. This question can be solved ...”
October 4, 2018
Brent@GMATPrepNow posted a reply to If p and q are prime numbers, is pq+1 an odd number? in the Data Sufficiency forum
“Be careful, deloitte247 You haven''t used the information about p and q being prime numbers. Cheers, Brent”
October 4, 2018
Brent@GMATPrepNow posted a reply to In the figure above, A is the center of the circle, DF is 5, in the Problem Solving forum
“As you can see from my solution above, this question is a time-killer (even if you answer it correctly!!) So, if you''re running short on time, you can reduce the correct answers to two options, and make your best guess How so? IMPORTANT: the diagrams in GMAT problem solving questions are DRAWN ...”
October 4, 2018
Brent@GMATPrepNow posted a reply to In the figure above, A is the center of the circle, DF is 5, in the Problem Solving forum
“As you can see from my solution above, this question is a time-killer (even if you answer it correctly) So, if you''re running short on time, you can reduce the correct answers to two options, and make your best guess How so? IMPORTANT: the diagrams in GMAT problem solving questions are DRAWN TO ...”
October 4, 2018
Brent@GMATPrepNow posted a reply to In the figure above, A is the center of the circle, DF is 5, in the Problem Solving forum
“Let x = the length of AF https://i.imgur.com/pT36mTR.png This means AD = x + 5 = radius of the circle. This is convenient, because AE is also a radius of the circle. So, AE must have length x + 5 https://i.imgur.com/aLGqKow.png At this point, we can focus on the RIGHT TRIANGLE below: ...”
October 4, 2018
Brent@GMATPrepNow posted a reply to If p and q are prime numbers, is pq+1 an odd number? in the Data Sufficiency forum
“ Given: p and q are prime numbers Target question: Is pq + 1 an odd number? This is a good candidate for rephrasing the target question. In order for pq + 1 to be odd, we need pq to be EVEN So, we COULD rephrase our target question as Is pq an even number?, but we can do even better than ...”
October 4, 2018
Brent@GMATPrepNow posted a reply to A political candidate collected $1,749 from a fund raising in the Problem Solving forum “In order to MAXIMIZE the number of contributors, we must MINIMIZE the amount that each supporter contributes. So, let''s say that each supporter contributes exactly$50 (which is the minimum about that each supporter contributes) $50 divides into$1,749 a total of 34 times (with $49 left over). ...” October 4, 2018 Brent@GMATPrepNow posted a reply to If x^2 + 3x + 3 = 5x + 6 then x equals in the Problem Solving forum “nonplus2''s approach is the as mine, but a reasonably fast alternative approach is to test the answer choices . Answer choice A suggests that one possible solution is x = -1 So, plug x = -1 into the equation to get: (-1)² + 3(-1) + 3 = 5(-1) + 6 Simplify to get: 1 = 1. Perfect!!! So, x = -1 ...” October 4, 2018 Brent@GMATPrepNow posted a reply to A thin piece of wire 40 meters long is cut into two pieces. in the Problem Solving forum “One approach is to plug in a value for r and see what the output should be. Let''s say r = 0. That is, the radius of the circle = 0 This means, we use the entire 40-meter length of wire to create the square. So, the 4 sides of this square will have length 10, which means the area = 100 So, ...” October 4, 2018 Brent@GMATPrepNow posted a reply to The price of a phone call consists of a standard connection in the Problem Solving forum “A 10-minute call costs$2.90 and a 16-minute call costs $4.40$4.40 - $2.90 =$1.50, and 16 minutes - 10 minutes = 6 minutes So, the extra $1.50 paid for extra 6 minutes of calling So,$0.75 would pay for 3 minutes of calling How much does a 13-minute call cost? A 10-minute call costs ...”
October 4, 2018
Rich.C@EMPOWERgmat.com posted a reply to A hiker walking at a constant rate of 4 miles per hour is in the Problem Solving forum
“Hi All, We''re told that a hiker walking at a constant rate of 4 miles per hour is passed by a cyclist traveling in the same direction along the same path at a constant rate of 20 miles per hour. the cyclist stops & waits for the hiker 5 minutes after passing her while the hiker continues to ...”
October 4, 2018
Rich.C@EMPOWERgmat.com posted a reply to The weights of four packages are 1, 3, 5, and 7pounds, in the Problem Solving forum
“Hi All, We''re told that the weights of four packages are 1, 3, 5, and 7 pounds, respectively. We''re asked which of the following CANNOT be the total weight, in pounds, of ANY combination of the packages. This question comes down to basic Arithmetic - and you might find that it''s easiest to ...”
October 4, 2018
Rich.C@EMPOWERgmat.com posted a reply to If Max can complete a job in 4 hours and Nick can complete in the Problem Solving forum
“Hi All, We''re told that Max can complete a job in 4 hours and Nick can complete the same job in 6 hours. We''re asked how many FEWER hours it would take Max and Nick working together to complete the job than Max alone needs to complete the job. This question can be solved in a couple of ...”
October 4, 2018
Rich.C@EMPOWERgmat.com posted a reply to 580 (Q44 V26) to 670 (Q45 V37) in 2 months! in the I just Beat The GMAT! forum
“Hi auljaj, A 670/Q45 is a strong score - and a fantastic improvement over your first attempt! When are you planning to apply to Business School? And what Schools are you planning to apply to? Congrats again on all of your success so far! Another GMAT Assassin has been made! Rich”
October 4, 2018
Brent@GMATPrepNow posted a reply to How many ounces of water must be added to 10 ounces of 3 % in the Problem Solving forum
“The original solution contains 10 ounces 3% of that is alcohol 3% of 10 = 0.3 So, the original solution contains 0.3 ounces of alcohol Let x = the amount of water (in ounces) that must be added So, the volume of the RESULTING solution = 10 + x ounces IMPORTANT: Since we''re adding water ...”
October 3, 2018
Brent@GMATPrepNow posted a reply to Ken has a group of coins worth $6.70. He has four times as m in the Problem Solving forum “Let x = the NUMBER of dimes So, 4x = the NUMBER of nickels And 4x - 20 = the NUMBER of quarters One dime is worth$0.1, so 0.10x = the total VALUE of the dimes (in dollars) Likewise, (0.05)(4x) = the total VALUE of the nickels (in dollars) And (0.25)(4x - 20) = the total VALUE of the ...”
October 3, 2018
Brent@GMATPrepNow posted a reply to Goku and Vegeta are waiting in a line, are there more than 1 in the Data Sufficiency forum
“Target question: Are there more than 10 people waiting in the line? Head straight to... Statements 1 and 2 combined There are several scenarios that satisfy BOTH statements. Here are two: Case a: BACK A, B, C, D, Vegeta, Picollo, Goku, E, F, G, H FRONT. In this case, the answer to the ...”
October 3, 2018
Brent@GMATPrepNow posted a reply to Vivian drives to her sister's house and back. She takes the in the Problem Solving forum
“One approach is to assign a "nice" value (one that works well with 50 mph and 70 mph) to the distance her sister''s house. So, let''s say the distance is 350 miles Average speed = (total distance traveled)/(total travel time) TOTAL distance = 350 miles + 350 miles = 700 miles ...”
October 3, 2018
Brent@GMATPrepNow posted a reply to Tom’s Mom is five times as old as him. In 6 years, Tom’ in the Problem Solving forum
“Tom’s Mom is five times as old as him. Let T = Tom''s PRESENT age So, 5T = Mom''s PRESENT age This also means: Let T + 6= Tom''s age IN 6 YEARS and 5T + 6 = Mom''s age IN 6 YEARS In 6 years, Tom’s Mom will be three times as old as Tom. In other words: (Mom''s age IN 6 YEARS) = ...”
October 3, 2018
Brent@GMATPrepNow posted a reply to A “descending number” is a three-digit number, such that in the Problem Solving forum
“Let''s use some counting methods to solve this. P(selected number is "descending") = total # of descending numbers/total # of 3-digit numbers total # of 3-digit numbers 3-digit numbers go from 100 to 999 inclusive A nice rule says: the number of integers from x to y inclusive ...”
October 3, 2018
Rich.C@EMPOWERgmat.com posted a reply to A garden center sells a certain grass seed in 5-pound bags in the Problem Solving forum
“Hi All, We''re told that a garden center sells a certain grass seed in 5-pound bags at $13.85 per bag, 10-pound bags at$20.43 per bag, and 25-pound bags at $32.25 per bag. We''re asked, if a customer is to buy AT LEAST 65 pounds of the grass seed, but NO MORE THAN 80 pounds, what is the least ...” October 3, 2018 Rich.C@EMPOWERgmat.com posted a reply to If Machine X can make 40 widgets in 8 minutes, how many in the Problem Solving forum “Hi All, We''re told that Machine X can make 40 widgets in 8 minutes. We''re asked for the number of widgets it can make in 1 hour. This question is a straight-forward rate question and you can probably see that you can quickly determine the rate (in widgets/minute) of the Machine. 40 ...” October 3, 2018 Rich.C@EMPOWERgmat.com posted a reply to During a two-week period, the price of an ounce of silver in the Problem Solving forum “Hi All, We''re told that during a two-week period, the price of an ounce of silver INCREASED by 25 percent by the end of the first week and then DECREASED by 20 percent of this new price by the end of the second week. We''re asked, if the price of silver was X dollars per ounce at the beginning ...” October 3, 2018 Rich.C@EMPOWERgmat.com posted a reply to Last year, Andre's company gave him a year-end bonus that in the Problem Solving forum “Hi All, We''re told that last year, Andre''s company gave him a year-end bonus that was between$160 and $200 and this year, his year-end bonus was 200% GREATER than it was the previous year. We''re asked which of the following COULD be the value of Andre''s bonus this year, rounded to the ...” October 2, 2018 Rich.C@EMPOWERgmat.com posted a reply to The price of a phone call consists of a standard connection in the Problem Solving forum “Hi All, We''re told that the price of a phone call consists of a standard connection fee, which is constant, plus a per minute charge, a 10-minute call costs$2.90 and a 16-minute call costs $4.40. We''re asked for the cost of a 13-minute call. This question can be solved in a couple of ...” October 2, 2018 Brent@GMATPrepNow posted a reply to Challenge question: If y < 0 < x, is x/y > -1? in the Data Sufficiency forum “I checked the link you provided, Fabio. For me, the response from the test-makers that sticks out the most is this: "it is highly unlikely that you would come across a question with independently sufficient statements that contradict each other" I think the person answering the ...” October 2, 2018 Brent@GMATPrepNow posted a reply to Challenge question: If y < 0 < x, is x/y > -1? in the Data Sufficiency forum “My apologies. I posted my question without noticing its FATAL FLAW. KEY CONCEPT: On the GMAT, the two statements in a Data Sufficiency question will never contradict each other (for more on this, see the video below) Let''s examine the main issue. Statement 1: x + y > 0 Okay, so x + ...” October 2, 2018 Brent@GMATPrepNow posted a reply to During a two-week period, the price of an ounce of silver in the Problem Solving forum “Another approach is to test a "nice" value x A great value would be$80 (since we get $100 after we increase$80 by 25%) So, x = $80 In other words, the price of silver was$80 per ounce at the beginning of the two-week period. During a two-week period, the price of an ounce of ...”
October 2, 2018
Brent@GMATPrepNow posted a new topic called Challenge question: If y < 0 < x, is x/y > -1? in the Data Sufficiency forum
“If y < 0 < x, is x/y > -1? (1) x + y > 0 (2) 3x < -2y Answer: D Difficulty level: 600 - 650 Source: www.gmatprepnow.com”
October 2, 2018
Brent@GMATPrepNow posted a reply to For all values of x and y , let x&y be defined by x& in the Problem Solving forum
“Nice question! GIVEN: x&y = xy − x + 1 So, take the equation: (a − 2)&a = a&(a + 1) Apply rules to get the equation: (a - 2)(a) - (a - 2) + 1 = (a)(a + 1) - a + 1 Expand: a² - 2a - a + 2 + 1 = a² + a - a + 1 Simplify: a² - 3a + 3 = a² + 1 Subtract a² from both sides ...”
October 2, 2018
Brent@GMATPrepNow posted a reply to If 3 different numbers are selected from the first 8 prime n in the Problem Solving forum
“The first 8 prime numbers are: {2, 3, 5, 7, 11, 13, 17, 19} Notice that only one prime number is EVEN, and the remaining seven numbers are ODD. Also notice that the sum of 3 numbers will be EVEN only if one of the three selected numbers is 2 So, the question is really asking "What is the ...”
October 2, 2018
Brent@GMATPrepNow posted a reply to The symbol Ω represents one of the following operations: ad in the Data Sufficiency forum
“Target question: What is the value of 1 Ω 1? Given: Ω represents one of the following operations: addition, subtraction, multiplication or division. Statement 1: 2 Ω 2 = 4 2 - 2 = 0, so Ω CANNOT represent subtraction. 2 ÷ 2 = 1, so Ω CANNOT represent division. 2 + 2 = 4, so ...”
October 2, 2018
Brent@GMATPrepNow posted a reply to On a 20 mile course, Pat bicycled at an average rate of 30 in the Problem Solving forum
“Let''s start with a WORD EQUATION (Distance traveled at 30 mph) + (Distance traveled at 8 mph) = 20 miles Distance = (rate)(time) Let t = the time (in hours) Pat spent running at 8 mph Aside: 12 minutes = 1/5 hours So, we get: (30 miles per hour)(1/5 hours) + (8 miles per hour)(t ...”
October 2, 2018
Brent@GMATPrepNow posted a reply to The greatest common factor of 16 and the positive integer n in the Problem Solving forum
“Now, we can use ELIMINATION to find the correct answer. Goal: Find GCF of 210 and n. 210 = (2)(3)(5)(7) The greatest common factor of 16 and the positive integer n is 4 16 = (2)(2)(2)(2) 4 = (2)(2) So, we know for certain that the PRIME FACTORIZATION of n has TWO 2''s (and no more than ...”
October 2, 2018
Brent@GMATPrepNow posted a reply to Jan lives x floors above the ground floor of a highrise in the Problem Solving forum
“Let''s first convert 7 minutes to SECONDS in order to have uniform units of measurement. 7 minutes = 420 seconds Let''s start with a word equation Jan''s travel time (in seconds) WALKING down = Jan''s travel time (in seconds) via ELEVATOR + 420 seconds It takes her 30 seconds per floor to ...”
October 1, 2018
Rich.C@EMPOWERgmat.com posted a reply to Working continuously 24 hours a day, a factory bottles Soda in the Problem Solving forum
“Hi All, We''re told that working continuously 24 hours a day, a factory bottles Soda Q at a rate of 500 liters per second and Soda V at a rate of 300 liters per second and that TWICE as many bottles of Soda V as of Soda Q are filled at the factory each day. We''re asked for the ratio of the ...”
October 1, 2018
Rich.C@EMPOWERgmat.com posted a reply to Jan lives x floors above the ground floor of a highrise in the Problem Solving forum
“Hi All, We''re told that Jan lives X floors above the ground floor of a high-rise building; it takes her 30 SECONDS per floor to walk down the steps and 2 SECONDS per floor to ride the elevator. We''re asked if it takes Jan the SAME amount of time to walk down the steps to the ground floor as to ...”
October 1, 2018
Rich.C@EMPOWERgmat.com posted a reply to The figure above represents a rectangular tank. How many in the Problem Solving forum
“Hi All, We''re told that the figure above represents a rectangular tank (with a length of 1200 cm, a width of 960 cm and a height of 120 cm). We''re asked for the number of cubic centimeters of water are in the tank when the water level is 10 centimeters BELOW the top of the tank. This question ...”
October 1, 2018
Rich.C@EMPOWERgmat.com posted a reply to At a certain committee meeting only associate professors and in the Problem Solving forum
“Hi All, This question actually has a fantastic shortcut built into it that allows you to avoid almost all the long-winded math: Associates bring 2 pencils and 1 chart; a total of 3 items Assistants bring 1 pencil and 2 charts; a total of 3 items There are 10 pencils and 11 charts; a ...”
October 1, 2018
Brent@GMATPrepNow posted a reply to Five letters A, P, P, L and E are listed in a row. How many in the Problem Solving forum
“Here''s an approach that doesn''t require us to subtract the bad arrangements. Take the task of arranging the 5 letters and break it into stages. Stage 1: Arrange the letters A, L, E in a row We can arrange n unique objects in n! ways. So, we can arrange the 3 letters in 3! ways (= 6 ...”
October 1, 2018
Brent@GMATPrepNow posted a reply to Jevan must paint 3 rooms in a house. Room A can be painted in the Problem Solving forum
“Take the task of painting the 3 rooms and break it into stages. Stage 1: Select a color for Room A Room A can be painted orange, red or green So, we can complete stage 1 in 3 ways Stage 2: Select a color for Room B Room B can be painted orange, white or red. So we can complete this ...”
October 1, 2018
Brent@GMATPrepNow posted a reply to Improve My Overall Score in the Last Leg of Preparation? in the GMAT Strategy forum
“The resource labeled "OG2018" has questions from the 2018 OG See: https://www.beatthegmat.com/mba/official-guide-2018-library Cheers, Brent”
October 1, 2018
Brent@GMATPrepNow posted a reply to Improve My Overall Score in the Last Leg of Preparation? in the GMAT Strategy forum
“Look no further<i class="em em-grinning"></i> : https://www.beatthegmat.com/official-guide-question-library-t296755.html Cheers, Brent”
October 1, 2018
Brent@GMATPrepNow posted a reply to If m and n are integers, is mn an odd integer? in the Data Sufficiency forum
“Some important rules: #1. ODD +/- ODD = EVEN #2. ODD +/- EVEN = ODD #3. EVEN +/- EVEN = EVEN #4. (ODD)(ODD) = ODD #5. (ODD)(EVEN) = EVEN #6. (EVEN)(EVEN) = EVEN Target question: Is mn an odd integer? Given: m and n are integers Statement 1: m(n+1) is even Let''s test some ...”
October 1, 2018
Brent@GMATPrepNow posted a reply to If n is an integer, is n even? in the Data Sufficiency forum
“Some important rules: 1. ODD +/- ODD = EVEN 2. EVEN +/- ODD = ODD 3. EVEN +/- EVEN = EVEN 4. (ODD)(ODD) = ODD 5. (ODD)(EVEN) = EVEN 6. (EVEN)(EVEN) = EVEN Target question: Is integer n EVEN? Statement 1: n² - 1 is an odd integer n² - 1 = (n + 1)(n - 1) So, statement 1 is ...”
October 1, 2018
Rich.C@EMPOWERgmat.com posted a reply to Alice and Bruce each bought a refrigerator... in the Problem Solving forum
“Hi All, We''re told that Alice and Bruce each bought a refrigerator, and the sum of their purchases was $900. We''re also told that TWICE of what Alice paid was$75 MORE than what Bruce paid. We''re asked what did Alice paid for her refrigerator. This question can be solved in a couple of ...”
September 30, 2018
Rich.C@EMPOWERgmat.com posted a reply to Which of the following points is the intersection between in the Problem Solving forum
“Hi All, We''re asked which of the following points is the intersection between the lines y = 3x + 6 and y = -2x - 4. this question can be solved in a number of different ways. Sometimes, the fastest way to answer a question is to use ''brute force''; the five answers are co-ordinates and we know ...”
September 30, 2018
Rich.C@EMPOWERgmat.com posted a reply to If x and y are positive integers greater than 1 such that x in the Problem Solving forum
“Hi All, We''re told that X and Y are positive integers GREATER than 1 such that (X - Y) is an EVEN integer and X/Y is an EVEN integer. We''re asked which of the following numbers must be NON-PRIME integers. This question can be solved with a mix of Number Property rules and TESTing VALUES. To ...”
September 30, 2018
Rich.C@EMPOWERgmat.com posted a reply to A and B can complete a task in 20 days. B and C can complete in the Problem Solving forum
“Hi All, We''re told that A and B can complete a task in 20 days. B and C can complete the same task in 30 days and A and C can complete the task in 40 days. We''re asked to arrange the ''efficiencies'' of A, B, and C in descending order. This is actually more of a ''logic question'' than a ...”
September 30, 2018
Rich.C@EMPOWERgmat.com posted a reply to Last year, a certain public transportation system sold an in the Problem Solving forum
“Hi All, We''re told that last year, a certain public transportation system sold an average (arithmetic mean) of 41,000 tickets per day on weekdays (Monday through Friday) and an average of 18,000 tickets per day on Saturday and Sunday. We''re asked which of the following is closest to the total ...”
September 30, 2018
Rich.C@EMPOWERgmat.com posted a reply to The microcurrent through the electrode in a delicate circuit in the Problem Solving forum
“Hi All, We''re told that the microcurrent through the electrode in a delicate circuit is usually held constant at (3.6)(10^(-8)) amps and, because of a defect in another part of the circuit, the current was 1,000 times SMALLER. What was the current, in amps, caused by this defect. This question ...”
September 30, 2018
Rich.C@EMPOWERgmat.com posted a reply to Improve My Overall Score in the Last Leg of Preparation? in the GMAT Strategy forum
“Hi Mrrinali, GMAC has publicly stated that the Official Score that you earn on Test Day is within +/- 30 points of actual ability. Assuming a similar ''swing'' in how your CATs function, your 2 CAT score results show that you essentially performed the same each time (about 630 +/- a few points). ...”
September 30, 2018
Brent@GMATPrepNow posted a reply to When positive integer n is divided by 13, the remainder is 2 in the Problem Solving forum
“When it comes to remainders, we have a nice rule that says: If N divided by D leaves remainder R, then the possible values of N are R, R+D, R+2D, R+3D,. . . etc. For example, if k divided by 5 leaves a remainder of 1, then the possible values of k are: 1, 1+5, 1+(2)(5), 1+(3)(5), ...”
September 30, 2018
Brent@GMATPrepNow posted a reply to A marketing firm determined that, of 200 households surveyed in the Problem Solving forum
“We can also solve this question using the Double Matrix Method. Here, we have a population of 200 households , and the two characteristics are: - using or not using Brand A soap - using or not using Brand B soap So, we can set up our matrix as follows (where "~" represents ...”
September 30, 2018
Brent@GMATPrepNow posted a reply to Lindsay can paint 1/x of a certain room in 20 minutes. What in the Problem Solving forum
“Given: Lindsay can paint 1/x of a certain room in 20 minutes So, in 1 HOUR, Lindsay can paint 3/x of the room Given: Lindsay and Joseph can paint the room in 1 HOUR. During that one hour, Lindsay can paint 3/x of the room. So, during that 1 HOUR, Joseph must paint the rest (whatever Lindsay ...”
September 30, 2018
Brent@GMATPrepNow posted a reply to PS : In a certain clothing store in the Problem Solving forum
“Let C = price of one pair of the CHEAPEST socks So, 2C - 1 = price of one pair of the MOST EXPENSIVE socks A customer notices that for exactly $18, she can buy three fewer pairs of the most expensive socks than the cheapest socks. As a word equation, we can write: (# of pairs of EXPENSIVE ...” September 30, 2018 Brent@GMATPrepNow posted a reply to If x and y are positive integers, is x/y < (x+5)/(y+5)? in the Data Sufficiency forum “ Given: x and y are positive integers Target question: Is x/y < (x+5)/(y+5)? This is a good candidate for rephrasing the target question. Since y is POSITIVE, we can safely take the inequality x/y < (x+5)/(y+5) and multiply both sides by y. When we do this, we get: x < ...” September 30, 2018 Brent@GMATPrepNow posted a reply to If x is the greatest common factor of 36 and 96, what is the in the Problem Solving forum “Mitch''s solution is the approach I''d take, but another way to answer this question is to simply LIST the factors of each value and then find the GREATEST factor they have in common. When listing factors, it''s best to do so in pairs of values with a given product (either 36 or 96). Here''s what ...” September 30, 2018 Brent@GMATPrepNow posted a reply to If a photocopier makes 2 copies in 1313 second, then, at the in the Problem Solving forum “We can also solve this question with equivalent ratios We''ll first convert 4 minutes to SECONDS in order to use the same units of measurement throughout the solution. 1 minute = 60 seconds So, 4 minutes = 240 seconds. Now let''s set up and equation using the ratio # of copies/time in ...” September 30, 2018 Brent@GMATPrepNow posted a reply to A number of people each wrote down one of the first 30 posit in the Data Sufficiency forum “Target question: Were any of the integers written down by more than one of the people? Given: A number of people each wrote down one of the first 30 positive integers. Statement 1: The number of people who wrote down an integer was greater than 40. If there were exactly 30 people, ...” September 29, 2018 Brent@GMATPrepNow posted a reply to A computer programmer needs to print 148 documents. The in the Problem Solving forum “We can also answer this question using a step-by-step approach based on number sense. IMPORTANT: The word approximately typically suggests that we can be somewhat aggressive with our estimation There are 148 documents and the documents have an average length of 10 pages So, the TOTAL number ...” September 29, 2018 Brent@GMATPrepNow posted a reply to List M consists of 50 decimals, each of which has a value be in the Problem Solving forum “Let''s examine the EXTREME CASES S - T = x percent of T So, S - T = (x/100)T Divide both sides by to get: (S - T)/T = x/100 Multiply both sides by 100 to get: x = 100(S - T)/T First, we we''ll MINIMIZE the value of x by minimizing the value of S - T and maximizing the value of T. This ...” September 29, 2018 Brent@GMATPrepNow posted a reply to If a child flips a coin five times in a row, what is the in the Problem Solving forum “If a coin is flipped 5 times in a row, there are 32 possible outcomes (HHTTH, HTHTT, TTTTT, etc) How did we get 32? Well, there are 2 possible outcomes for the 1st coin flip, 2 possible outcomes for the 2nd coin flip, 2 outcomes for the 3rd flip, 2 outcomes for the 4th flip, and 2 outcomes for ...” September 29, 2018 Rich.C@EMPOWERgmat.com posted a reply to If x and y are integers, is the product xy odd? in the Data Sufficiency forum “Hi All, We''re told that X and Y are INTEGERS. We''re asked if (X)(Y) is ODD. This is a YES/NO question and can be solved with Number Properties and TESTing VALUES. 1) X = -5 With the information in Fact 1, we know the value of X (and that it''s ODD). However, we don''t know whether Y is ...” September 28, 2018 Rich.C@EMPOWERgmat.com posted a reply to If a, b & c are integers, is abc odd? in the Data Sufficiency forum “Hi AbhishekRyu, We''re told that A, B and C are INTEGERS. We''re asked if (A)(B)(C) is ODD. This is a YES/NO question and can be solved with Number Properties and TESTing VALUES. 1) (A)(B) is ODD Since A and B are both integers, the only way the product of those two numbers to be odd is ...” September 28, 2018 Brent@GMATPrepNow posted a reply to R and S can complete a certain job in 6 and 4 days in the Problem Solving forum “Let''s assign a "nice" value to the job, a value that works well with the given values (6 days and 4 days ). So, let''s say the ENTIRE job is to make 24 widgets R can complete a certain job in 6 days In other words, R can make 24 widgets in 6 days So, R can make 4 widgets per day ...” September 28, 2018 Rich.C@EMPOWERgmat.com posted a reply to The usage of sugar of a family of 3 adults and 2 children in the Problem Solving forum “Hi All, We''re told that the usage of sugar of a family of 3 adults and 2 children was 13 kg in a certain month and the monthly AVERAGE usage of sugar for an adult is 3 kg and for a child is 1 kg. We''re asked by what percent THIS specific month’s sugar consumption was more or less than the ...” September 28, 2018 Rich.C@EMPOWERgmat.com posted a reply to A lecture course consists of 595 students. The students are in the Problem Solving forum “Hi All, We''re told that a lecture course consists of 595 students and that the students are to be divided into discussion sections, each with an EQUAL number of students. We''re asked which of the following CANNOT be the number of students in a discussion section. This question is really just ...” September 28, 2018 Rich.C@EMPOWERgmat.com posted a reply to If x and y are different prime numbers, each greater than 2, in the Problem Solving forum “Hi All, We''re told that a X and Y are DIFFERENT PRIME numbers, each GREATER than 2. We''re asked which of the following must be true (which really means "which of these is ALWAYS true no matter how many different examples you can come up with?"). This question can be solved used ...” September 28, 2018 Rich.C@EMPOWERgmat.com posted a reply to A certain liquid passes through a drain at a rate of w/20 ga in the Problem Solving forum “Hi All, We''re told that a certain liquid passes through a drain at a rate of W/20 gallons every X SECONDS. We''re asked how many MINUTES it would take Y gallons to pass through the drain. This question can be solved in a number of different ways, including by TESTing VALUES. IF.... W=20 ...” September 28, 2018 Brent@GMATPrepNow posted a reply to An engagement team consists of a project manager, team in the Problem Solving forum “For this question, let''s first ignore the restriction regarding the two consultants who refuse to work together and find the total number of different teams. Then we''ll determine how many of those teams break the rule about the two consultants. In other words, # of "good" teams = ...” September 28, 2018 Rich.C@EMPOWERgmat.com posted a reply to Time for me to Stop Studying on my Own? - GMAT Quant Help in the GMAT Math forum “Hi andyaf, To start, a 500 is a decent initial CAT Score (the average Score on the Official GMAT hovers around 550 most years). That having been said, it will take a LOT of work to raise a 500 to 750+, and you''ll have to make significant improvements to how you handle BOTH the Quant and ...” September 27, 2018 Brent@GMATPrepNow posted a reply to In 2004, 2,400 condos sold, 15% of the total housing units in the Problem Solving forum “We can also solve this with a little number sense If 15% of the units sold WERE condos, then 85% of the units sold new NOT condos. GIVEN: 2,400 represents 15% of the total housing units sold that year So, 4,800 must represent 30% of the total housing units sold that year And 9,600 must ...” September 27, 2018 Brent@GMATPrepNow posted a reply to In 2004, 2,400 condos sold, 15% of the total housing units in the Problem Solving forum “We can solve the question with equivalent ratios If 15% of the units sold WERE condos, then 85% of the units sold new NOT condos. So we want to determine the number of sold units that represent 85% of all units sold We''ll use the ratio: (number of units sold)/(percent of units sold) Let x = ...” September 27, 2018 Rich.C@EMPOWERgmat.com posted a reply to At a dinner party 5 people are to be seated around a in the Problem Solving forum “Hi All, We''re told that 5 people are to be seated around a circular table and that two sitting arrangements are considered different only when the positions of the people are different relative to each other. We''re asked for the total number of possible sitting arrangements of the group. ...” September 26, 2018 Rich.C@EMPOWERgmat.com posted a reply to In Dives Corporation, 75% of the employees are customer in the Problem Solving forum “Hi All, We''re told that in the Dives Corporation, 75% of the employees are customer service representatives, 15% are programmers, and 10% are managers, the customer service representatives have an average salary of$60,000, and the programmers have an average salary of $100,000. We''re asked if ...” September 26, 2018 Brent@GMATPrepNow posted a reply to A set of numbers has an average of 50. If the largest elemen in the Problem Solving forum “The largest element is 4 greater than 3 times the smallest element Let x = the smallest number in the set. So, 3x + 4 = the largest number in the set. So, the set looks something like this {x, ?, ?, . . . . ?, 3x+4} The key to this question is that the AVERAGE = 50 Since all of the answer ...” September 26, 2018 Brent@GMATPrepNow posted a reply to A set of numbers has an average of 50. If the largest elemen in the Problem Solving forum “The largest element is 4 greater than 3 times the smallest element Let x = the smallest number in the set. So, 3x + 4 = the largest number in the set. So, the set looks something like this {x, ?, ?, . . . . ?, 3x+4} The key to this question is that the AVERAGE = 50 Since all of the answer ...” September 26, 2018 Rich.C@EMPOWERgmat.com posted a reply to In the xy-plane, if line k has negative slope, is the in the Data Sufficiency forum “Hi All, We''re told that in the xy-plane, Line K has NEGATIVE slope. We''re asked if the y-intercept of Line K is positive. This is a YES/NO question. It can be solved in a couple of different ways, including by TESTing VALUES. To start, with a negative slope, BOTH the x-intercept and ...” September 25, 2018 Rich.C@EMPOWERgmat.com posted a reply to 12 years out of college, GMAT study plan? in the GMAT Strategy forum “Hi KDR83, That''s great news - especially considering the time off you took over the Summer. To clarify things a bit though, was this a CAT that you had taken before (or did you see any questions on it that you had previously answered?)? GMAT assassins aren''t born, they''re made, Rich” September 25, 2018 Brent@GMATPrepNow posted a reply to The sequence Sn has the terms S1=1, S2=2, S3=6, S4=15, S5=31 in the Problem Solving forum “If you don''t spot a pattern, you can always TEST the answer choices We want to find Sn - Sn-1 So, let''s test a value of n. How about n = 2 So, we want to find the value of S2 - S1 Well, we''re told that S2 = 2 and S1 = 1 So, S2 - S1 = 2 - 1 = 1 So, when n = 2, the answer to the ...” September 25, 2018 Brent@GMATPrepNow posted a reply to A and B represent digits in the Problem Solving forum “I''m not saying that 68+8=86 I''m saying that, if A=6 and B=8, then our equation (AB + B = BA) becomes 68 + 8 = 86 Since this equation is faulty, we can eliminate answer choice B Cheers, Brent” September 24, 2018 Rich.C@EMPOWERgmat.com posted a reply to Machine A and Machine B can produce 1 widget in 3 hours work in the Problem Solving forum “Hi All, This question is a bit more complex than a typical Work question, but you can still use the Work Formula to solve it. Work = (A)(B)/(A+B) where A and B are the speeds of the two individual machines From the prompt, we know that Machine A and Machine B, working together, can produce ...” September 24, 2018 Rich.C@EMPOWERgmat.com posted a reply to If six coins are flipped simultaneously, the probability of in the Problem Solving forum “Hi All, We''re told that six coins are flipped simultaneously. We''re asked which probability is closest to getting AT LEAST one heads and AT LEAST one tails. This question comes down to a bit of probability math (which is essentially just about doing the necessary Arithmetic). With 6 coins, ...” September 24, 2018 Rich.C@EMPOWERgmat.com posted a reply to A conference room has two analog (12-hour format) clocks, in the Problem Solving forum “Hi All, We''re told that a conference room has two analog (12-hour format) clocks, one on the north wall and one on the south wall; the clock on the north wall LOSES 30 seconds per HOUR, and the clock on the south wall GAINS 15 seconds per HOUR. We''re asked, if the clocks begin displaying the ...” September 24, 2018 Rich.C@EMPOWERgmat.com posted a reply to A seller sold two shoes at the same selling price. If the in the Problem Solving forum “Hi All, We''re told that a seller sold two shoes at the SAME selling price; the percentage profit on one of the shoes was 30% and the percentage loss on the other shoe was 30%. We''re asked for the overall percentage profit or loss made by the seller. This question can be solved by TESTing ...” September 24, 2018 Brent@GMATPrepNow posted a reply to W, X, Y and Z each represent a different number. If the sum in the Problem Solving forum “KEY CONCEPT: The sum of all of the rows = The sum of all of the columns So, 3 + 6 + 9 + 0 = (-2) + 7 + n + 5 Solve: n = 8 Answer: C Cheers, Brent” September 24, 2018 Brent@GMATPrepNow posted a reply to If x^y = 1 then what is the in the Data Sufficiency forum “Target question: What is the value of x? Given: x^y = 1 If x^y = 1, then there are 3 possible cases: case i: x = 1, and y = any value (e.g., 1^9 = 1) case ii: x = -1, and y = an even integer (e.g., (-1)^4 = 1) case iii: x = any non-zero value, and y = 0 (e.g., 7^0 = 1) Statement ...” September 23, 2018 Brent@GMATPrepNow posted a reply to If 893 × 78 = p, which of the following is equal to 893 × in the Problem Solving forum “Given: 893 x 78 = P 893 x 79 = 893 x (78 + 1) = (893)(78) + (893)(1) = P + 893 = D Cheers, Brent” September 23, 2018 Brent@GMATPrepNow posted a reply to In an office that employs 120 people, m% of the employees in the Data Sufficiency forum “I thought I''d point out that the two approaches above are known as the Double Matrix Method. This technique can be used for most questions featuring a population in which each member has two characteristics associated with it. Here, we have a population of students, and the two characteristics ...” September 22, 2018 Brent@GMATPrepNow posted a reply to The shaded region in the figure above represents a in the Problem Solving forum “IMPORTANT: the diagrams in GMAT problem solving questions are DRAWN TO SCALE unless stated otherwise. So, we can use this fact to solve the question by simply "eyeballing" the diagram. See our video below on this topic as well as other assumptions we can make about diagrams on the ...” September 21, 2018 Rich.C@EMPOWERgmat.com posted a reply to clarification on GMAT 2016 DS problem in the Data Sufficiency forum “Hi All, We''re told that a taxi company charges F cents for the first mile of the taxi ride and M cents for each additional mile. We''re asked how much the company charges for a 10 mile taxi ride. This question can be solved with a mix of Algebra and TESTing VALUES. 1) The company charges ...” September 21, 2018 Brent@GMATPrepNow posted a reply to Challenge question: If ∆ABC is an isosceles triangle in the Data Sufficiency forum “Target question: What is the perimeter of ∆ABC? Given: ∆ABC is an isosceles triangle Statement 1: AB = 10√3 We only know the measurement of ONE side of the triangle. So, there''s no way to determine the triangle''s perimeter. Since we cannot answer the target question with ...” September 20, 2018 Brent@GMATPrepNow posted a reply to Challenge question: If ∆ABC is an isosceles triangle in the Data Sufficiency forum “Thanks Fabio! I fixed it. Cheers, Brent” September 20, 2018 Brent@GMATPrepNow posted a reply to If Albert can travel 200 miles in 4 hours, how many hours in the Problem Solving forum “Another approach is to apply some number sense GIVEN: Albert can travel 200 miles in 4 hours This means: Albert can travel 100 miles in 2 hours And: Albert can travel 50 miles in 1 hour 350 miles = 200 miles + 100 miles + 50 miles So, the time to travel 350 miles = 4 hours + 2 hours + 1 ...” September 20, 2018 Rich.C@EMPOWERgmat.com posted a reply to If 12 men and 16 women can do a piece of work in 5 days and in the Problem Solving forum “Hi All, We''re told that 12 men and 16 women can do a piece of work in 5 days and 13 men and 24 women can do it in 4 days. We''re asked how long it will take 7 men and 10 women to complete that same task. This question can be approached in a couple of different ways (some of which involve a lot ...” September 20, 2018 Brent@GMATPrepNow posted a reply to In four years, Andy will be twice as old as Betsy. How old in the Data Sufficiency forum “ Given: In four years, Andy will be twice as old as Betsy. Let A = Andy''s PRESENT age Let B = Betsy''s PRESENT age So, A+4 = Andy''s age IN 4 YEARS And so, B+4 = Betsy''s age IN 4 YEARS If Andy will be twice as old as Betsy IN 4 YEARS, we can write: A+4 = 2(B+4) Expand: A + 4 = 2B + 8 ...” September 20, 2018 Brent@GMATPrepNow posted a reply to What is the perimeter of a rectangle? in the Data Sufficiency forum “Target question: What is the perimeter of a rectangle? This is a good candidate for rephrasing the target question. Let x = the length of the rectangle''s base Let y = the length of the rectangle''s height So, the perimeter of the rectangle = 2x + 2y REPHRASED target question: What is the ...” September 20, 2018 Brent@GMATPrepNow posted a reply to How many multiples of 33 lie between 101 and 1,000, inclusiv in the Problem Solving forum “Another approach is to apply the following rule: If x and y are multiples of k, then the number of multiples of k from x to y inclusive = So, for example, the multiples of 3 from 6 to 21 inclusive = 6 So, the number of multiples of 33 from 132 to 990 inclusive = (990 - 132)/33 + 1 = 858/33 ...” September 20, 2018 Brent@GMATPrepNow posted a reply to How many multiples of 33 lie between 101 and 1,000, inclusiv in the Problem Solving forum “Some positive multiples of 33 are: 33, 66, 99, 132, 165, 198,. . . , 957, 990, 1023 So, we want the number of multiples of 33 from 132 to 990 inclusive Observe: 132 = (33)(4) 165 = (33)(5) 198 = (33)(6) . . . 957 = (33)(29) 990 = (33)(30) We can see that the number of multiples of ...” September 20, 2018 Rich.C@EMPOWERgmat.com posted a reply to The Malibu Country Club needs to drain its pool for in the Problem Solving forum “Hi All, We''re told that a The Malibu Country Club needs to drain its pool for refinishing. The hose they use to drain it can remove 60 cubic feet of water per MINUTE, the pool is 80 feet wide by 150 feet long by 10 feet deep and is currently at 80% full. We''re asked how long it will, in HOURS, ...” September 20, 2018 Rich.C@EMPOWERgmat.com posted a reply to Bobby bought 2 shares, and which he sold for$96 each. If he in the Problem Solving forum
“Hi All, We''re told that Bobby bought 2 shares, which he sold for $96 each, he had a profit of 20% on the sale of one of the shares but a loss of 20% on the sale of the other share. We''re asked to find the TOTAL profit or loss on the sale of the two shares. This question essentially comes down ...” September 20, 2018 Rich.C@EMPOWERgmat.com posted a reply to A driver paid n dollars for auto insurance for the year in the Problem Solving forum “Hi All, We''re told that a driver paid N dollars for auto insurance for the year 1997. This annual premium was raised by P percent for the year 1998, then for EACH of the years 1999 and 2000, the premium was decreased by 1/6 from the previous year’s figure, leaving the driver’s insurance ...” September 20, 2018 Rich.C@EMPOWERgmat.com posted a reply to If a mixture of ground meat consists of 2 pounds of veal in the Problem Solving forum “Hi All, We''re told that a mixture of ground meat consists of 2 pounds of veal that costs X dollars per pound, and 5 pounds of beef that costs Y dollars per pound. We''re asked for the cost, in dollars, per pound of the mixture. This question can be approached in a number of different ways, ...” September 20, 2018 Brent@GMATPrepNow posted a reply to Last year's receipts from the sale of candy on Valentine's in the Problem Solving forum “GIVEN: 385 million dollars represents 7% of TOTAL candy sales In other words: 7% of TOTAL candy sales = 385 million dollars Rewrite as: (7/100)(TOTAL candy sales) = 385 million To multiply both sides by 100/7 to get: TOTAL candy sales = (100/7)(385 million) ASIDE: We need not perform any ...” September 20, 2018 Brent@GMATPrepNow posted a reply to In the coordinate plane, line M travels through points in the Problem Solving forum “KEY CONCEPT: In a straight line with slope m, any segment of the line will have slope m. To get from point (9, 10) to point (0, 4), we start at (9, 10) and move 9 spaces to the left and 6 spaces down to get to (0, 4) Let''s keep going. Starting at (0, 4), we can, once again, move 9 spaces ...” September 20, 2018 Brent@GMATPrepNow posted a reply to If x and y are different prime numbers, each greater than 2, in the Problem Solving forum “Some important rules: #1. ODD +/- ODD = EVEN #2. ODD +/- EVEN = ODD #3. EVEN +/- EVEN = EVEN #4. (ODD)(ODD) = ODD #5. (ODD)(EVEN) = EVEN #6. (EVEN)(EVEN) = EVEN If x and y are different prime numbers, each greater than 2 . . . Since all prime numbers (EXCEPT 2) are ODD, this statement ...” September 19, 2018 Brent@GMATPrepNow posted a reply to How many 3 digit numbers can we make such that two of the in the Problem Solving forum “There are 3 cases to consider: case 1) numbers of the form XXY (1st and 2nd digits are the same and the 3rd digit is different) case 2) numbers of the form XYX (1st and 3rd digits are the same and the 2nd digit is different) case 3) numbers of the form YXX (2nd and 3rd digits are the same and the ...” September 19, 2018 Brent@GMATPrepNow posted a reply to In 2001, John invest x dollars ina special account that in the Problem Solving forum “ John$250 in his account in 2006 and in 2008 he has $270 in his account, So, in 2 years, John''s balance increases by$20 So, the balance increases $10 EACH YEAR In 2001, John invests x dollars in a special account that yields y% simple interest annually John''s balance increases$10 EACH ...”
September 19, 2018
Brent@GMATPrepNow posted a reply to GMAT Official Guide - Probability googly in the Problem Solving forum
“P(selecting a sibling pair) = P(select a junior with a sibling AND select the senior who is that junior''s sibling) = P(select a junior with a sibling) x P(select the senior who is that junior''s siblingx 1/800 = 60/800,000 = 3/40,000 = A Note: P(select a junior with a sibling) = 60/1000, ...”
September 19, 2018
Brent@GMATPrepNow posted a reply to Which of the following decribes all values of n for which in the Problem Solving forum
“Another approach is to test values and eliminate answer choices For example, one value of n that satisfies the equation n² - 1 ≥ 0 is n = 2 Notice that 2² - 1 = 4 - 1 = 3 and 3 ≥ 0 Now check the answer choices. . . Answer choice B says that n CANNOT equal 2 (since it says n ≤ 1) As ...”
September 19, 2018
Brent@GMATPrepNow posted a reply to In the figure above, what is the distance from point P to in the Problem Solving forum
“Once we create our right triangle with sides 1/2, 1/2 and x (the hypotenuse), we can apply the Pythagorean Theorem to get: (1/2)² + (1/2)² = x² Expand: 1/4 + 1/4 = x² So, 1/8 = x² This means x = √(1/8) Check the answer choices. . . .√(1/8) is not there. Looks like we need to simplify ...”
September 19, 2018
Brent@GMATPrepNow posted a reply to If six coins are flipped simultaneously, the probability of in the Problem Solving forum
“When it comes to probability questions involving "at least," it''s best to try using the complement. That is, P(Event A happening) = 1 - P(Event A not happening) So, here we get: P(getting at least one heads and at least one tails) = 1 - P(not getting at least one heads and at least one ...”
September 19, 2018
Brent@GMATPrepNow posted a reply to If n is an integer, is n(n+2) divisible by 8? in the Data Sufficiency forum
“Target question: Is n(n+2) divisible by 8? Statement 1: n is an even number. Let''s examine some CONSECUTIVE even numbers: 6, 8, 10, 12, 14, 16, 18, 20, 22, etc Notice that the numbers increase by 2 with each subsequent value. So, if n is EVEN, then we know that n+2 is also even. Also, ...”
September 19, 2018
Brent@GMATPrepNow posted a new topic called Challenge question: If ∆ABC is an isosceles triangle in the Data Sufficiency forum
“If ∆ABC is an isosceles triangle, what is the perimeter of ∆ABC? (1) AB = 10√3 (2) AC = 8 Answer: C Difficulty level: 600 - 650 Source: www.gmatprepnow.com”
September 19, 2018
Rich.C@EMPOWERgmat.com posted a reply to Which of the following decribes all values of n for which in the Problem Solving forum
“Hi All, We''re asked which of the following describes all values of N for which (N^2 - 1) is greater than or equal to 0. This question can be solved in a couple of different ways, but you might find it easiest to TEST VALUES. Since we''re SQUARING the value of N, we know that there will be ...”
September 19, 2018
Rich.C@EMPOWERgmat.com posted a reply to A basket contains 5 apples, of which 1 is spoiled and the in the Problem Solving forum
“Hi All We''re told that we have 4 regular apples and 1 spoiled apple. We''re asked - if you grab 2 apples, then what''s the probability of getting the spoiled apple? The question can be solved in a couple of ways. Here''s how to track each of the different outcomes that matches what we''re ...”
September 19, 2018
Rich.C@EMPOWERgmat.com posted a reply to Oscar is running in a straight line away from Nancy at the in the Problem Solving forum
“Hi All, We''re told that Oscar is running in a straight line away from Nancy at the rate of 20 feet per second, Nancy is chasing Oscar at the rate of 25 feet per second and Oscar has a 100-foot head start. We''re asked for the number of seconds it will it take Nancy to catch Oscar. This is an ...”
September 19, 2018
Brent@GMATPrepNow posted a reply to Challenge question: If 40 percent more than 40 percent of x in the Problem Solving forum
“--------ASIDE-------------------- 40% MORE THAN k = k + (40% of k) = k + 0.4x = 1.4x 40% LESS THAN Q = Q - (40% of Q) = Q - 0.4Q = 0.6Q ----NOT ONTO THE QUESTION!!----------- 40 percent of x is the same as 0.4x So, 40 percent more than 40 percent of x is the same as (1.4)(0.4x) ...”
September 18, 2018
Brent@GMATPrepNow posted a reply to In how many ways a cricket team consisting of 5 batsmen, 4 in the Problem Solving forum
“Take the task of creating a cricket team and break it into stages. Stage 1: Select 5 batsmen Since the order in which we select the batsmen does not matter, we can use combinations. We can select 5 batsmen from 7 batsmen in 7C5 ways (21 ways) So, we can complete stage 1 in 21 ways ...”
September 18, 2018
Brent@GMATPrepNow posted a reply to Which of the following functions satisfies f(a+b)=f(a)f(b) f in the Problem Solving forum
“Another approach is to a = 1 and b = 1 So, with each function, is it true that f(1 + 1) = f(1)f(1)? In other words, is it true that f(2) = f(1)f(1)? A. f(x) = x + 1 Is it true that f(2) = f(1)f(1)? Plug values into the function to get: 2 + 1 = (1 + 1)(1 + 1) Simplify: 3 = 4 No good. ...”
September 18, 2018
Brent@GMATPrepNow posted a reply to a and b are positive numbers. What is the value of (a-b)/(a+ in the Data Sufficiency forum
“Target question: What is the value of (a - b)/(a + b)? Statement 1: a = 2b Take: (a - b)/(a + b) Replace a with 2b to get: (2b - b)/(2b + b) Simplify: b/3b Divide top and bottom by b to get: 1/3 So, the answer to the target question is (a - b)/(a + b) = 1/3 Since we can answer the ...”
September 18, 2018
Brent@GMATPrepNow posted a reply to Which of the following functions satisfies f(a+b)=f(a)f(b) f in the Problem Solving forum
“Upon scanning the answer choices, we might recognize that answer choice E, f(x) = 2^x, involves a variable exponent and that the given information that f(a+b) = f (a)f(b) looks A LOT like the Product Law: (k^a)(k^b) = k^(a+b) So, let''s check E first. E. f(x) = 2^x If f(x) = 2^x, then f(a) = ...”
September 18, 2018
Brent@GMATPrepNow posted a reply to A certain business school has a student body of 2,000 studen in the Data Sufficiency forum
“I thought I''d point out that Jay''s approach is also known as the Double Matrix Method. This technique can be used for most questions featuring a population in which each member has two characteristics associated with it. Here, we have a population of students, and the two characteristics are: ...”
September 18, 2018
Rich.C@EMPOWERgmat.com posted a reply to In each of five taste tests, each of 51 participants chose in the Data Sufficiency forum
“Hi All, We''re told that in each of 5 taste tests, each of 51 participants chose either Brand X or Brand Y. The brand chosen by the majority of participants in a taste test was the winner of that taste test, and the brand that won the majority of the taste tests was deemed the better brand. ...”
September 17, 2018
Rich.C@EMPOWERgmat.com posted a reply to Two gardeners, Burton and Philips in the Problem Solving forum
“Hi All, We''re told that two gardeners, Burton and Philips, work at independent constant rates to prune a garden full of roses. If both gardeners start at the same time and work at their normal rates, they will complete the job in 45 minutes. However, if Philips were to work at TWICE Burton''s ...”
September 17, 2018
Rich.C@EMPOWERgmat.com posted a reply to Going in to the last game of his basketball season, Adrian in the Problem Solving forum
“Hi All, We''re told that going in to the last game of his basketball season, Adrian had averaged 24 points per game and in his last game, he scored 50 points (bringing his average to 26 points per game for the season). We''re asked for the TOTAL number of games Adrian played that season. This ...”
September 17, 2018
Rich.C@EMPOWERgmat.com posted a reply to Grandmother's Punch hangover cure is a mix of two in the Problem Solving forum
“Hi All, We''re told that Grandmother''s Punch hangover cure is a mix of two ingredients: a herbal extraction that contains 20% alcohol and apricot cider that contains 5% alcohol. We''re asked if a 750-milliliter Grandmother''s Punch bottle has 87 milliliters of alcohol, how much apricot cider ...”
September 17, 2018
Brent@GMATPrepNow posted a reply to Going in to the last game of his basketball season, Adrian in the Problem Solving forum
“Let G = total number of games that Adrian played in the ENTIRE season Going in to the last game of his basketball season, Adrian had averaged 24 points per game. At this point, Adrian has played G-1 games So, we can write: (total number of points in G-1 games)/(G-1) = 24 Multiply both sides ...”
September 17, 2018
Brent@GMATPrepNow posted a new topic called Challenge question: If 40 percent more than 40 percent of x in the Problem Solving forum
“If 40 percent more than 40 percent of x is equal to 40 percent less than y, what is the value of x/y? A) 3/8 B) 15/16 C) 1 D) 15/14 E) 15/4 Answer: D Difficulty level: 600 – 650 Source: www.gmatprepnow.com”
September 17, 2018
Brent@GMATPrepNow posted a reply to What is the perimeter of isosceles triangle LMN? 1) Side LM in the Data Sufficiency forum
“Target question: What is the perimeter of isosceles triangle LMN? Jump to. . . . Statements 1 and 2 combined There are two triangles that satisfy BOTH statements. They are: Case a: The side lengths of triangle LMN are 4, 4 and 4√2. In this case, the answer to the target question is ...”
September 17, 2018
Brent@GMATPrepNow posted a reply to 2^p/2^q=? in the Data Sufficiency forum
“Target question: What is the value of (2^p)/(2^q) ? This is a good candidate for rephrasing the target question. Aside: Here’s a video with tips on rephrasing the target question: Take: (2^p)/(2^q) Apply the Quotient law to get: 2^(p - q) This means (2^p)/(2^q) = 2^(p - q) So, in order ...”
September 17, 2018
Brent@GMATPrepNow posted a reply to Counting question in the Ask the Test Maker forum
“Good catch! (someone else just alerted me to my error) I have edited my response accordingly. Cheers, Brent”
September 17, 2018
Rich.C@EMPOWERgmat.com posted a reply to What is the perimeter of isosceles triangle LMN? 1) Side LM in the Data Sufficiency forum
“Hi All, We''re told that triangle LMN is an isosceles triangle. We''re asked for the PERIMETER of that triangle. 1) Side LM has a length of 4 With the information in Fact 1, we know that one (or possibly two) of the sides of this isosceles triangle, but we don''t know all 3 sides, so ...”
September 17, 2018
Brent@GMATPrepNow posted a reply to If 4x − 3y = 13 and 5x + 2y = −1, then x = in the Problem Solving forum
“Given: 4x − 3y = 13 5x + 2y = −1 Take the top equation and multiply both sides by 2 Take the bottom equation and multiply both sides by 3 We get: 8x − 6y = 26 15x + 6y = −3 Add the two equations to get: 23x = 23 Solve: x = 1 Answer: C Cheers, Brent”
September 17, 2018
Brent@GMATPrepNow posted a reply to If the ratio of the present age of Anna and Paula is 3:4 in the Problem Solving forum
“Here''s a nice property of fractions: If a, b and k are positive, then (a + k)/(b + k) approaches 1 as k gets bigger. For example, the fraction (2+11)/(3+11) is closer to 1 than 2/3 is. Likewise, the fraction (1+7)/(2+7) is closer to 1 than 1/2 is. Let A = Anna''s present age Let P = Paula''s ...”
September 16, 2018
Brent@GMATPrepNow posted a new topic called If x^y = 1 then what is the in the Data Sufficiency forum
“If x^y = 1, then what is the value of x? (1) x < 0 (2) y is even integer”
September 16, 2018
Brent@GMATPrepNow posted a reply to When Leo imported a certain item, he paid a 7 percent import in the Problem Solving forum
“Here''s a step-by-step algebraic solution. Let T = the TOTAL value of the item. Leo paid a 7% import tax on the portion of the total value of the item in EXCESS of $1000 So, Leo pays tax on the amount that''s GREATER then$1000 So, Leo pays 7% tax on (T - 1000) We can write: import tax = ...”
September 16, 2018
Brent@GMATPrepNow posted a reply to A rectangular-shaped carpet remnant that measures x feet in the Problem Solving forum
“Area of rectangle = (base)(height) = (x feet)(y feet) = xy square feet GIVEN: 9 square feet = 1 square yard So, we can also say that 1 square foot = 1/9 square yards So, xy square feet = xy/9 square YARDS So, if xy/9 square YARDS cost $50, then each square YARD =$50/(xy/9) = ...”
September 16, 2018
Brent@GMATPrepNow posted a reply to Bob drives at an average rate of 50 mph from Berkeley to Los in the Problem Solving forum
“As the others have shown, the fast approach is to recognize that: travel time = distance/speed = 350/50 = 7 hours However, we could also (if necessary) solve this by applying some common sense. Bob''s speed is 50 miles per hour. In other words, for every 1 hour that elapses, Bob travels 50 ...”
September 16, 2018
Brent@GMATPrepNow posted a reply to At what speed was Erik running when he was at the halfway in the Data Sufficiency forum
“IMPORTANT: The two statements essentially provide the exact same information. If it took Erik 2 hours to travel 10 miles, we can conclude that his average speed was 5 miles per hour. When the two statements provide the same information in a Data Sufficiency question, the correct answer must be ...”
September 15, 2018
Brent@GMATPrepNow posted a reply to Probability from GMAT prep in the Problem Solving forum
“The two approaches shown above are the best (faster) approaches, but here''s one more. Since there are so few objects involved (5 apples), we should be able to quickly answer the question by simply listing and counting Let A, B, C, D, and E represent the 5 apples, and let E represent the ...”
September 15, 2018
Brent@GMATPrepNow posted a reply to A zebra must get water from either a stream or pond. Which in the Data Sufficiency forum
“Unfortunately, we don''t know if the two ''constant rates'' that are mentioned are the same OR not, so there''s no way to gauge the relative distances to the stream and pond. IF the two rates are equal, then the distances of the two water sources would be the same. [/quote] Even if the ...”
September 14, 2018
Brent@GMATPrepNow posted a reply to A zebra must get water from either a stream or pond. Which in the Data Sufficiency forum
“Target question: Which of the two sources of water is closer to the zebra’s current position? Jump straight to.... Statements 1 and 2 COMBINED There are several scenarios that satisfy BOTH statements. Here are two: Case a: When traveling to the STREAM, the zebra heads EAST in a ...”
September 14, 2018
Brent@GMATPrepNow posted a reply to Taking the GMAT in four days. Need advice calming my nerves in the GMAT Strategy forum
“You''re certainly not the first person to get nervous during this high-stakes (and expensive) test! If you''re interested, we have a free video on the topic on overcoming test anxiety: [url]http://www.gmatprepnow.com/module/general-gmat-strategies/video/1252[/url] Also, as part of managing ...”
September 14, 2018
Brent@GMATPrepNow posted a reply to If 1/n(n+1) = 1/n – 1/(n+1), then what is the value of 1/( in the Problem Solving forum
“If 1/n(n+1) = 1/n – 1/(n+1), then... 1/(1*2) = 1/1 - 1/2 1/(2*3) = 1/2 - 1/3 1/(3*4) = 1/3 - 1/4 . . . 1/(98*99) = 1/98 - 1/99 1/(99*100) = 1/99 - 1/100 So, 1/(1*2) + 1/(2*3) + 1/(3*4) + … + 1/(99*100) = (1/1 - 1/2) + (1/2 - 1/3) + (1/3 - 1/4) + . . . (1/98 - 1/99) + (1/99 - ...”
September 14, 2018
Brent@GMATPrepNow posted a reply to Is x < 0? in the Data Sufficiency forum
“Target question: Is x < 0? Statement 1: |x| = -x Let''s TEST some values. There are several values of x that satisfy statement 1. Here are two: Case a: x = -1. Notice that |-1| = -(-1). In this case, the answer to the target question is YES, x IS less than 0 Case b: x = 0. Notice that ...”
September 14, 2018
Rich.C@EMPOWERgmat.com posted a reply to A zebra must get water from either a stream or pond. Which in the Data Sufficiency forum
“Hi All, We''re told that a zebra must get water from either a stream or pond. We''re asked which of the two sources of water is closer to the zebra’s current position. 1) Moving at a constant rate, it takes the zebra 2 hours to reach the stream from its current position. Fact 1 tells ...”
September 14, 2018
Rich.C@EMPOWERgmat.com posted a reply to Taking the GMAT in four days. Need advice calming my nerves in the GMAT Strategy forum
“Hi Varun, In these last few days, you should NOT try to do too much work (NO ''cramming" and NO CATs). You would be best served by doing some general review and keeping your studies light. Try to get some extra rest so that you can go into Test Day calm, clear-headed and ready to work. As ...”
September 14, 2018
Brent@GMATPrepNow posted a reply to If n is an integer, is (n+1)^2 an even integer? in the Data Sufficiency forum
“Some important rules: 1. ODD +/- ODD = EVEN 2. ODD +/- EVEN = ODD 3. EVEN +/- EVEN = EVEN 4. (ODD)(ODD) = ODD 5. (ODD)(EVEN) = EVEN 6. (EVEN)(EVEN) = EVEN Target question: Is (n+1)² an even integer? This is a good candidate for rephrasing the target question. Aside: Here’s a video ...”
September 13, 2018
Brent@GMATPrepNow posted a reply to Jack bought five mobiles at an average price of $150. The in the Problem Solving forum “Jack bought five mobiles at an average price of$150. So, (sum of all 5 mobiles)/5 = $150 Multiply both sides by 5 to get: sum of all 5 mobiles =$750 The median of all the prices is $200. Let a = smallest value Let b = 2nd smallest value Let d = largest value Let c = 2nd largest value ...” September 13, 2018 Brent@GMATPrepNow posted a reply to A driver paid n dollars for auto insurance for the year in the Problem Solving forum “First recognize that INCREASING a value by p percent is the same as multiplying by (100 + p)/100 For example, increasing a value by 7% is the same as multiplying by (100 + 7)/100 Likewise, increasing a value by 25% is the same as multiplying by (100 + 25)/100 Also, recognize that DECREASING a ...” September 13, 2018 Brent@GMATPrepNow posted a reply to To furnish a room in a model home, an interior decorator is in the Problem Solving forum “Total # of combinations = (# of ways to select 2 chairs)(# of ways to select 2 tables) So, 150 = (# of ways to select 2 chairs)(# of ways to select 2 tables) # of ways to select 2 chairs 5 tables, choose 2 of them. Since the order of the selected chairs does not matter, we can use ...” September 13, 2018 Brent@GMATPrepNow posted a reply to How many positive two-digit numbers yield a remainder of 1 in the Problem Solving forum “When it comes to remainders, we have a nice rule that says: If N divided by D leaves remainder R, then the possible values of N are R, R+D, R+2D, R+3D,. . . etc. For example, if k divided by 5 leaves a remainder of 1, then the possible values of k are: 1, 1+5, 1+(2)(5), 1+(3)(5), ...” September 13, 2018 Brent@GMATPrepNow posted a reply to good farming (OG13 71) in the Sentence Correction forum “(A) good growing conditions both encouraged farming traditions that, in places, endure in The word COMBINATION implies that the two conditions combine to have an effect. So, the word BOTH is redundant. ELIMINATE A (B) good growing conditions encouraged farming traditions that have, in places, ...” September 12, 2018 Brent@GMATPrepNow posted a reply to What is the biggest positive integer which will always divid in the Problem Solving forum “One approach is to list integers in the form n, n+1 and n+2 such that n is even, and look for a pattern... 2, 3, 4 Product = 24, which is divisible by 2, 3, 6, 12 and 24 4, 5, 6 Product = 120, which is divisible by 2, 3, 6, 12 and 24 6, 7, 8 Product = 336, which is divisible by 2, 3, 6, ...” September 12, 2018 Brent@GMATPrepNow posted a reply to If the interior angles of a triangle are in the ratio 3 to in the Problem Solving forum “Oops, good catch! I have edited my response accordingly. Cheers and thanks, Brent” September 12, 2018 Brent@GMATPrepNow posted a reply to Flor is choosing three of five colors of paint to use for he in the Problem Solving forum “Jay''s approach is the approach that I''d typically use. However, it''s important to note that, when the answer choices are so small (as they are here), we should also consider the straightforward strategy of listing and counting Let R, B, P, G and Y represent the colors Red, Blue, Purple, Green ...” September 12, 2018 Brent@GMATPrepNow posted a reply to If the interior angles of a triangle are in the ratio 3 to in the Problem Solving forum “All 3 angles must add to 180° So, if we divide 180° into 3 angles in the ratio 3 : 4 : 5, we get: 45° : 60° : 75° What is the measure of the largest angle? The largest angle is 75 degrees° Answer: D Cheers, Brent” September 12, 2018 Brent@GMATPrepNow posted a reply to Is p + pz = p? in the Data Sufficiency forum “Target question: Is p + pz = p? This is a great candidate for rephrasing the target question. Aside: Here’s a video with tips on rephrasing the target question: Take Is p + pz = p? and subtract p from both sides to get: Is pz = 0? In order for pz to equal 0, it must be the case that ...” September 12, 2018 Brent@GMATPrepNow posted a reply to A company plans to assign identification numbers to its in the Problem Solving forum “Take the task of creating the identification numbers and break it into stages. Stage 1: Select the first digit of the identification number The first digit can be 1, 2, 3, 4, 5, 6, 7, 8, or 9 So, we can complete stage 1 in 9 ways Stage 2: Select the second digit of the identification ...” September 12, 2018 Rich.C@EMPOWERgmat.com posted a reply to Each baseball team in a league has a roster of players in in the Problem Solving forum “Hi All, We''re told that each baseball team in a league has a roster of players in the ratio of 2 pitchers for every 3 fielders, each team has a total of 25 players on its roster and there are 12 total teams in the league. We''re asked for the DIFFERENCE between the total number of fielders and ...” September 12, 2018 Rich.C@EMPOWERgmat.com posted a reply to A certain library assesses fines for overdue books as in the Problem Solving forum “Hi All, This question includes a ''conditional statement'' that effects how you''re supposed to handle each "step" in the math: "for each additional day....., the total fine is EITHER increased by 30 cents OR doubled, whichever results in the LESSER AMOUNT." Since ...” September 12, 2018 Rich.C@EMPOWERgmat.com posted a reply to Kevin drove from A to B at a constant speed of 60 mph. Once in the Problem Solving forum “Hi All, We''re told that Kevin drove from A to B at a constant speed of 60 mph, then he turned right around without pause, and returned to A at a constant speed of 80 mph. In addition, exactly 4 hours before the end of his trip, he was STILL approaching B, only 15 miles away from it. We''re ...” September 12, 2018 Brent@GMATPrepNow posted a reply to Last week Chris earned x dollars per hour for the first 40 in the Problem Solving forum “If Chris worked 48 hours, then he was paid 40x dollars for first 40 hours and (8)(22) dollars for the next 8 hours Since Chris earned$816, we can write: 40x + (8)(22) = 816 Simplify: 40x + 176 = 816 Subtract 176 from both sides: 40x = 640 Solve: x = 640/40 = 16 Answer: D Cheers, Brent”
September 11, 2018
Brent@GMATPrepNow posted a reply to If x is even integer, which of the following must be an odd in the Problem Solving forum
“A quick approach is the plug in a even number for x and see what happens. A super easy number to use us x = 0 We get..... A) (3)(0)/2 = 0, which is NOT odd. ELIMINATE A. B) (3)(0)/2 + 1 = 1, which IS odd. KEEP B. C) (3)(0)² = 0, which is NOT odd. ELIMINATE C. D) (3)(0²)/2 = 0, which ...”
September 11, 2018
Brent@GMATPrepNow posted a reply to The perimeter of a rectangular garden is 360 ft. What is the in the Data Sufficiency forum
“Great research, Mitch! I can''t imagine there are many official questions that hinge entirely on that one (somewhat esoteric) construct. I mean, for the every question you cited, it doesn''t matter which side we call the length or the width. The correct answer is the same in all cases. It''s ...”
September 11, 2018
Brent@GMATPrepNow posted a reply to The perimeter of a rectangular garden is 360 ft. What is the in the Data Sufficiency forum
“Interesting. I''ve never heard of that construct. So, for a box with dimensions 3 x 4 x 5, then the side with length 5 is the length? Which dimension is the width? What about cases when the terms base and height are used? Which one is the base? In a way, this reminds me of the times when ...”
September 11, 2018
Brent@GMATPrepNow posted a reply to The aerth travels around the sun at a speed of approximately in the Problem Solving forum
“Another way to deal with calculating (18.5)(3600) is to use the answer choices to our advantage. First off, there''s a nice rule that says: AB = (2A)(0.5B) This strategy (which is covered in this video: https://www.gmatprepnow.com/module/general-gmat-strategies/video/1113) can sometimes save us ...”
September 11, 2018
Brent@GMATPrepNow posted a reply to What is the value of 22C19? in the Problem Solving forum
“Good point! I should have mentioned that I use a shortcut for calculating combinations that allows me to perform most calculations in my head. For example, for 22C3, I write the first 3 values of 22! in the numerator, and I write the 3! in the denominator So, 22C3 = (22)(21)(20)/(3)(2)(1) ...”
September 11, 2018
Brent@GMATPrepNow posted a reply to What is the value of 22C19? in the Problem Solving forum
“When calculating combinations, it''s sometime useful to apply the following rule: nCr = nC(n-r). In other words, "n choose r" is equal to "n choose n - r" So, for example: 10C7 = 10C3 12C9 = 12C3 8C7 = 8C1 etc. Here''s why this property works: Let''s say you have 22 ...”
September 11, 2018
Brent@GMATPrepNow posted a reply to The perimeter of a rectangular garden is 360 ft. What is the in the Data Sufficiency forum
“To my test-prep colleagues. I have to say that I''m a little surprised by the official answer (D). For statement 2, it could be the case that length = 120 and width = 60, OR it could be the case that length = 60 and width = 120 The assumption here is that the length of a rectangle must be ...”
September 11, 2018
Brent@GMATPrepNow posted a reply to Which of the following points could lie in the same quadrant in the Problem Solving forum
“Let''s test some coordinates... How about: a = 1 and b = -2. This means the point (a, b) = (1, -2), which is in QUADRANT IV Now plug a = 1 and b = -2 into each answer choice... A) (-b, -a) = -2), -1] = (2, -1), which is also in QUADRANT IV PERFECT! Answer: A Cheers, Brent”
September 11, 2018
September 10, 2018
Brent@GMATPrepNow posted a reply to The sum of the ages of Doris and Fred is y years. If Doris in the Problem Solving forum
“Let F = Fred''s PRESENT age Doris is 12 years older than Fred. In other words, Doris'' age = F + 12. So, the sum of their ages = F + (F + 12) Simplify to get: sum of their ages = 2F + 12 The sum of the ages = y 2F + 12 = y Now solve for Fred''s age (F). Start with: 2F + 12 = y ...”
September 10, 2018
Brent@GMATPrepNow posted a reply to In the figure, ABCD is a square, and all the dots are in the Problem Solving forum
“If the vertical or horizontal distance between two adjacent dots is 3 units, then the square has dimensions 12 by 12 So, the area of the ENTIRE SQUARE = (12)(12) = 144 Now, notice that the square is comprised of 32 identical triangles https://i.imgur.com/mHC9rOY.png Since 16 of the triangles ...”
September 10, 2018
Brent@GMATPrepNow posted a reply to Is xy>0? in the Data Sufficiency forum
“Target question: Is xy > 0? Statement 1: x³y > 0 Since x² is POSITIVE, we can safely divide both sides of the inequality by x² When we do this, we get xy > 0 So, the answer to the target question is YES, xy IS greater than 0 Since we can answer the target question with ...”
September 10, 2018
Brent@GMATPrepNow posted a reply to If the circle above has center O and circumference 18π, the in the Problem Solving forum
“The circle has circumference 18π circumference = (2)(radius)(π) So, (2)(radius)(π) = 18π Solve to get: radius = 9 So, OR = 9 and OT = 9 Now, we''ll deal with arc RST Here the sector angle = 60° 60°/360° = 1/6 So, the arc RST represents 1/6 of the ENTIRE circle Since the ENTIRE ...”
September 10, 2018
Brent@GMATPrepNow posted a reply to Any decimal that has only a finite number of nonzero digits in the Data Sufficiency forum
“Target question: Is r/s a terminating decimal? Statement 1: 90 < r < 100 There are several pairs of values that meet this condition. Here are two: Case a: r = 91 and s = 2, in which case r/s = 91/2 = 45.5 = a terminating decimal Case b: r = 91 and s = 3, in which case r/s = 91/3 = ...”
September 10, 2018
Brent@GMATPrepNow posted a reply to In a certain pond, 50 fish were caught, tagged, and returned in the Problem Solving forum
“We can use equivalent ratios here. We''re told that the proportion of tagged fish in the 50-fish SAMPLE is equal to the the proportion of tagged fish in the ENTIRE pond. So, (# tagged fish in SAMPLE)/50 = (total # tagged fish)/(total # of fish in POND) Let x = # of fish in the entire ...”
September 10, 2018
Brent@GMATPrepNow posted a reply to permutation/combination in the Problem Solving forum
“This question is a little too ambiguous to be an official GMAT question. Let''s say X, Y and Z represents 3 different songs. Is an album with song X first, song Y second and song Z third considered DIFFERENT FROM an album with song Z first, song X second and song Y third? The answer to this ...”
September 9, 2018
Brent@GMATPrepNow posted a reply to Sam's car was fined when he gave Joe and Peter a ride, so in the Problem Solving forum
“Hey Mitch, I think you answered the question "What was the cost of the fine?" (which IS, indeed, $48), but we''re asked to determine the dollar amount that Sam paid (=$20). Cheers, Brent”
September 9, 2018
Brent@GMATPrepNow posted a reply to On Monday morning a certain machine ran continuously at a un in the Data Sufficiency forum
“Here''s a similar question to practice with: https://www.beatthegmat.com/on-wednesday-morning-a-fortune-cookie-machine-ran-t301683.html Cheers, Brent”
September 9, 2018
Brent@GMATPrepNow posted a reply to Sam's car was fined when he gave Joe and Peter a ride, so in the Problem Solving forum
“Let F = the total cost of the fine Joe paid $3 more than 1/4 of the fine So, F/4 + 3 = the amount Joe paid Peter paid$3 less than 1/3 of the fine So, F/3 - 3 = the amount Peter paid Sam paid $4 less than 1/2 the fine So, F/2 - 4 = the amount Sam paid (amount Joe paid) + (amount Peter ...” September 8, 2018 Brent@GMATPrepNow posted a reply to What is the area of a triangle with the following vertices in the Problem Solving forum “Now that you know the technique, you can practice your speed with this one: http://www.beatthegmat.com/coordinate-geometry-t116975.html Cheers, Brent” September 8, 2018 Brent@GMATPrepNow posted a reply to In the xy-plane, the line k passes through the origin and in the Data Sufficiency forum “Target question: Is b (the y-coordinate of the point on the line) positive? Given: Line k passes through the origin and through the point (a,b) Statement 1: The slope of line k is negative There are several lines and points that satisfy statement 1. Here are two: Case a: ...” September 8, 2018 Brent@GMATPrepNow posted a reply to Out of 2 broken TV sets and 6 fixed TV sets in Joe's Fix-My- in the Problem Solving forum “There are 8 TV''s in total 2 are broken 6 are fixed We want to find P(at least one TV is broken) When it comes to probability questions involving at least, it''s often best to try using the complement. That is, P(Event A happening) = 1 - P(Event A not happening) So, here we get: P(getting ...” September 8, 2018 Brent@GMATPrepNow posted a reply to what percent were stockholders who were not employees? in the Problem Solving forum “Let''s use the Double Matrix Method. This technique can be used for most questions featuring a population in which each member has two characteristics associated with it (aka overlapping sets questions). Here, we have a population of attendees, and the two characteristics are: - stockholder ...” September 7, 2018 Brent@GMATPrepNow posted a reply to Geometry and Angles (My weakness) in the Problem Solving forum “Here''s an idea of what''s going on.... https://i.imgur.com/Deg4te0.png When we compare the big triangle with the BASE 30-60-90 special triangle (which you must memorize for test day!), we can see that the hypotenuse of the big triangle is 35 times as long as the hypotenuse of the base triangle. ...” September 7, 2018 Brent@GMATPrepNow posted a reply to Digging in sediments in northern China, evidence has been in the Sentence Correction forum “Important: When a sentence begins with a with noun modifier (as it does in the above sentence), stop at the comma and ask the question that the modifier raises. So, once we read, Digging in sediments in northern China, we should stop and ask . . . "Who or what was digging in ...” September 7, 2018 Brent@GMATPrepNow posted a reply to OG City Council Member Q in the Critical Reasoning forum “PREMISE: Electricity demands increase 1.5% per year PREMISE: No space to build more power plants CONCLUSION: We must use LESS electricity through ordinances Strategy #1: Try to think of an assumption that''s required for the conclusion to logically follow from the premises. Notice that ...” September 7, 2018 Brent@GMATPrepNow posted a reply to Working simultaneously and independently at an identical con in the Problem Solving forum “Let''s assign a nice value to x (a value that will work well with all of the numbers 3, 4 and 6. Let''s say x = 24 GIVEN: 4 machines make x units in 6 days This means 4 machines make 24 units in 6 days So, 4 machines make 4 units in 1 day So, 1 machine makes 1 unit in 1 day From here, ...” September 7, 2018 Brent@GMATPrepNow posted a reply to What is the value of the 2-digit positive integer n if its in the Data Sufficiency forum “Target question: What is the value of the 2-digit positive integer n Given: Its tens digit is four times its units digit This is VERY LIMITING information. In fact, this tells us that EITHER n = 41 OR n = 82 There are no other possible values of n. Statement 1: n is an even number ...” September 7, 2018 Brent@GMATPrepNow posted a reply to A refrigerator holds a number of apples, bananas, carrots an in the Data Sufficiency forum “Be careful. If you feel that the ratio A : B : C : D = 2x : 5x : 3x : 7x, then you''d be able to answer the target question WITHOUT using any statements. Cheers, Brent” September 7, 2018 Brent@GMATPrepNow posted a reply to Which of the following points is the intersection between in the Problem Solving forum “KEY CONCEPT: The point of intersection (call P) of the lines y = 3x + 6 and y = -2x - 4 will be such that the x- and y-coordinates of P will satisfy BOTH equations. Since both equations are set equal to y, we can write: 3x + 6 = -2x - 4 Add 2x to both sides: 5x + 6 = - 4 Subtract 6 from both ...” September 7, 2018 Brent@GMATPrepNow posted a reply to If a mixture of ground meat consists of 2 pounds of veal in the Problem Solving forum “We can use the WEIGHTED AVERAGE formula: Weighted average of groups combined = (group A proportion)(group A average) + (group B proportion)(group B average) + (group C proportion)(group C average) + ... When we COMBINE the meats, the TOTAL weight = 2 + 5 = 7 pounds. So, veal comprises 2/7 of ...” September 7, 2018 Brent@GMATPrepNow posted a reply to Last year the price per share of Stock X increased by k in the Problem Solving forum “One approach is to plug in values. Let$100 be the original price per share of Stock X Choose a "nice" value for k. How about k = 200 So, after a 200% increase, the new price per share = $300 Let$100 be the original earnings per share of Stock X Choose a "nice" ...”
September 6, 2018
Brent@GMATPrepNow posted a reply to If 3x + 2y = -2z, what is x? in the Data Sufficiency forum
“Target question: What is the value of x? Given: 3x + 2y = -2z Notice that the two statements have the variables all on the left side of the equation. So, let''s rearrange our given equation to look the same. Take: 3x + 2y = -2z Add 2z to both sides to get: 3x + 2y + 2z = 0 Statement ...”
September 6, 2018
Brent@GMATPrepNow posted a reply to The selling price of an article is equal to the cost of the in the Data Sufficiency forum
“Let C = cost of article Target question: The markup on a certain television set is what percent of the selling price? Statement 1: The markup on the television set is 25 percent of the cost. If C = cost of article, markup = 0.25C Selling price = cost + markup = C + 0.25C = 1.25C So, ...”
September 6, 2018
Brent@GMATPrepNow posted a reply to Last year, a certain public transportation system sold an in the Problem Solving forum
“The word "closest" suggests that we can use some estimation here. Let''s first estimate the number of tickets sold PER WEEK 41,000 tickets per day on weekdays (5)(41,000) = 205,000 18,000 tickets per day on weekends (2)(18,000) = 36,000 So, total tickets sold PER WEEK = ...”
September 5, 2018
Brent@GMATPrepNow posted a reply to In the xy-coordinate system, line k has slope 1/2 and passes in the Problem Solving forum
“While a sample size of 28 might not be a large enough to make prove/validate my recommendations, I can tell you that, from my experience, the correct answer to these kinds of questions is typically closer to E than to A. That said, if it were the case that, with this question type, the correct ...”
September 5, 2018
Brent@GMATPrepNow posted a reply to In the figure above, what is the perimeter of rectangle ABPQ in the Data Sufficiency forum
“Target question: What is the perimeter of rectangle ABPQ? Statement 1: The area of rectangular region ABCD is 3 times the area of rectangular region ABPQ. Since we aren''t given any information regarding ACTUAL lengths, we cannot determine the perimeter of rectangle ABPQ Since we cannot ...”
September 5, 2018
Brent@GMATPrepNow posted a reply to The numbers x and y are NOT integers. The value of x is in the Data Sufficiency forum
“Target question: The value of x is closest to which integer? Let''s head straight to........... Statements 1 and 2 combined There are several values of x and y that satisfy BOTH statements. Here are two: Case a: x = 2.4 and y = 1.4. These values satisfy both statements. In this case, ...”
September 5, 2018
Brent@GMATPrepNow posted a reply to An insurance company sells only one type of health and one in the Data Sufficiency forum
“Let H = the number of health insurance policies Let L = the number of life insurance policies Let p = the monthly premium on a life insurance policy So, 80H + pL = 5000 Target question: What is the value of p? Statement 1: The total revenue from health insurance premiums was 4/5 of ...”
September 5, 2018
Brent@GMATPrepNow posted a reply to 8 cities, including Memphis, are finalists to be chosen to in the Data Sufficiency forum
“Target question: What is the probability that Memphis is not chosen? ASIDE: At first glance, it may seem like we already have enough information the answer the target question. After all, if there are 8 cities, then P(Memphis is chosen) = 1/8, which means Memphis is not chosen) = 7/8, right? ...”
September 5, 2018
Brent@GMATPrepNow posted a reply to In the xy-coordinate system, line k has slope 1/2 and passes in the Problem Solving forum
“Let''s first determine the equation of line k A quick approach is the write the equation of line k in slope y-intercept form: y = mx + b, where m = slope and b = y-intercept. We''re told that the slope = 0.5 and the point (0,5) tells us that the y-intercept is 5 So, the equation of line k is: ...”
September 5, 2018
Brent@GMATPrepNow posted a reply to A certain company assigns employees to offices in such a way in the Problem Solving forum
“ASIDE: When the answer choices are small, you should also consider listing and counting Let X, Y and Z be the 3 employees. Let A and B be the 2 offices. We''ll list the possible outcomes as follows: (employees in office A | employees in office B) So, we get: ( XYZ | -- ) ( XY |Z ) ( XZ ...”
September 5, 2018
Brent@GMATPrepNow posted a reply to A certain company assigns employees to offices in such a way in the Problem Solving forum
“Let X, Y and Z be the 3 employees. Let A and B be the 2 offices. Take the task of assigning the employees and break it into stages. Stage 1: Assign employee X to an office There two options (office A or office B), so we can complete stage 1 in 2 ways Stage 2: Assign employee Y to an ...”
September 5, 2018
Brent@GMATPrepNow posted a reply to A baker makes chocolate cookies and peanut cookies. His in the Problem Solving forum
“We''re looking for the smallest possible number of chocolate chip cookies. So, let''s start by testing answer choice A A) If we make 7 chocolate chip cookies, then the remaining 88 cookies are peanut cookies. We''re told that peanut cookies are baked in batches of 6 However, 88 is NOT ...”
September 4, 2018
Brent@GMATPrepNow posted a reply to If x and y are integers, what is the least possible positive in the Problem Solving forum
“Another approach: There''s a nice rule that says: If j, k and d are integers, and j is a multiple of d, and k is a multiple of d, then (j+k) must be a multiple of d 21x is a multiple of 7 (since 21x = 7(3x) 35y is a multiple of 7 (since 35y = 7(5y) Since 21x and 35y are multiples of 7, the ...”
September 4, 2018
Brent@GMATPrepNow posted a reply to If x and y are integers, what is the least possible positive in the Problem Solving forum
“21x + 35y = 7(3x + 5y) Since x and y are INTEGERS, we know that 3x and 5y are each INTEGERS, which means 3x + 5y equals some integer So, we can write: 21x + 35y = 7(some integer) In other words, 21x + 35y is a multiple of 7 Check the answer choices.....only D is a multiple of 7 Answer: D ...”
September 4, 2018
Brent@GMATPrepNow posted a reply to standard deviation in the Data Sufficiency forum
“Target question: Is the standard deviation of the set positive? KEY CONCEPT: If all of the numbers in a set are EQUAL, then the standard deviation = 0 If the numbers in a set are NOT all equal, then the standard deviation > 0 Given: The set consists of a certain number of even integers ...”
September 4, 2018
Brent@GMATPrepNow posted a reply to permutation/combination in the Problem Solving forum
“Here''s an algebraic solution... Let M = TOTAL number of men (including Mr. Smith) at the party Let W = TOTAL number of women (including Mrs. Smith) at the party Since Mr. Smith does not shake hands with HIMSELF, Mr. Smith shakes hands with M-1 men, and he shakes hands with W women Since ...”
September 4, 2018
Brent@GMATPrepNow posted a reply to Andrew has a certain number of coins in his pocket. He has in the Problem Solving forum
“Let x = number of QUARTERS in pocket So, 0.25x = VALUE of quarters in pocket He has three times as many dimes as quarters So, 3x = number of DIMES in pocket So, 0.10(3x) = 0.3x = VALUE of dimes in pocket He has six times as many nickels as dimes. So, (6)(3x) = number of NICKELS in ...”
September 4, 2018
Brent@GMATPrepNow posted a reply to Triathlete Dan runs along a 2-mile stretch of river and then in the Problem Solving forum
“Average speed = (total distance)/(total time) We know the total distance = 4 miles The total time consists of two parts: Let''s begin with a "word equation" TOTAL time = (time spent running) + (time spent swimming) time = distance/speed So, time spent running = 2/10 = 1/5 hours ...”
September 4, 2018
Brent@GMATPrepNow posted a reply to At a garage sale, all of the prices of the items sold were in the Problem Solving forum
“The price of the radio was the 15th highest price So, there were 14 items that were more expensive than the radio. In other words, if we listed all of the prices in ascending order, we''d get something like: ........... radio, X, X, X, X, X, X, X, X, X, X, X, X, X, X The price of the radio ...”
September 4, 2018
Brent@GMATPrepNow posted a reply to The average television prime-time advertising unit of 30 in the Problem Solving forum
“We can also quickly solve this question by testing the answer choices.... Start with C (40%) 40% of $30,000 =$12,000 So, a 40% increase (from 1973 to 1977) = $30,000 +$12000 = $42,000 No good. We need to new amount to be$50,000 ELIMINATE C Since $42,000 is less than$50,000, we need a ...”
September 4, 2018
Brent@GMATPrepNow posted a reply to Each of the following numbers has a remaider of 2 when in the Problem Solving forum
“ASIDE: This is one of those questions that require us to check/test each answer choice. In these situations, always check the answer choices from E to A, because the correct answer is typically closer to the bottom than to the top. For more on this strategy, see my article: ...”
September 4, 2018
Brent@GMATPrepNow posted a reply to At a certain hospital, 75% of the interns receive fewer than in the Problem Solving forum
“I thought I''d point out that Mitch''s Double Matrix approach can be used for most questions featuring a population in which each member has two characteristics associated with it. Here, we have a population of interns, and the two characteristics are: - less than 6 hours sleep or 6 or more ...”
September 4, 2018
Brent@GMATPrepNow posted a reply to DS_Arithmetic in the Data Sufficiency forum
“Target question: What is the tenth digit in the decimal representation of a certain number? Jump straight to..... Statements 1 and 2 combined Statement 1 tells us that the number is less than 1/3 (aka 0.333333....) Statement 2 tells us that the number is greater than 1/4 (aka 0.25) ...”
September 4, 2018
Rich.C@EMPOWERgmat.com posted a reply to The variable x takes on integer values between 1 and 7 in the Problem Solving forum
“Hi All, We''re told that the variable X takes on integer values between 1 and 7 inclusive as shown above (meaning that out of a total of 15 values, there are three 1s, one 2, three 3s, one 4, etc.). We''re asked for the probability that the absolute value of the DIFFERENCE between the MEAN (re: ...”
September 4, 2018
Rich.C@EMPOWERgmat.com posted a reply to Standard Deviation Problem in the Problem Solving forum
“Hi All, We''re told that for a certain examination, a score of 58 was 2 standard deviations BELOW the mean and a score of 98 was 3 standard deviations ABOVE the mean. We''re asked for the mean score for the examination. The math behind this question is just basic Algebra, but depending on how ...”
September 4, 2018
Rich.C@EMPOWERgmat.com posted a reply to GMAT PREP ? (TableSpoons) in the Problem Solving forum
“Hi All, We''re told that 3 teaspoons = 1 tablespoon and 4 tablespoons = 1/4 cup. We''re asked for the number of teaspoons that are equal to 3/8 cup. This question is a big ''unit conversion'' question and includes a big ''design shortcut'' that you can use to avoid most of the math. To start, ...”
September 4, 2018
Brent@GMATPrepNow posted a reply to permutation/combination in the Problem Solving forum
“This question is a little too ambiguous to be a true (official) GMAT question. Does order matter here? For example, is E driving, A in passenger seat, G in middle of back seat, and C in left side of back seat DIFFERENT FROM C driving, A in passenger seat, E in middle of back seat, and G in left ...”
September 3, 2018
Brent@GMATPrepNow posted a reply to A store sold 6 bicycles with an average sale price of $1,000 in the Data Sufficiency forum “Target question: What was the price of the most expensive bicycle? Given: The store sold 6 bicycles with an average sale price of$1,000. This means the SUM of the 6 bikes = $6000 (since$6000/6 bikes = $1000 average) Statement 1: The median price was$1,000. This statement doesn''t ...”
September 3, 2018
Brent@GMATPrepNow posted a reply to Alex paid a $12 fee to receive a 10% discount off of the in the Problem Solving forum “IMPORTANT: If Alex received a 10% discount, then Alex PAID 90% of the cost of the books If Victor received a 15% discount, then Victor PAID 85% of the cost of the books Start with a word equation Total amount Alex paid = Total amount Victor paid We get:$12 + 90% of b = $15 + 85% of b ...” September 3, 2018 Brent@GMATPrepNow posted a reply to Paula and Sandy were among those people who sold raffle in the Data Sufficiency forum “Target question: How many of the tickets did Paula sell? Given: Paula and Sandy sold a total of 100 of the tickets Let x = number of tickets that Paula sold This means 100-x = number of tickets that Sandy sold Statement 1: Sandy sold 2/3 as many of the raffle tickets as Paula did. We ...” September 3, 2018 Brent@GMATPrepNow posted a reply to Six children — A, B, C, D, E, and F — are going to sit i in the Problem Solving forum “Here are a few similar questions to practice with: - http://www.beatthegmat.com/permutation-t261691.html - http://www.beatthegmat.com/vowels-and-consonants-arrangement-t149946.html - http://www.beatthegmat.com/how-many-possible-orders-t277574.html Cheers, Brent” September 3, 2018 Rich.C@EMPOWERgmat.com posted a reply to Alex paid a$12 fee to receive a 10% discount off of the in the Problem Solving forum
“Hi All, We''re told that Alex paid a $12 fee to receive a 10% discount off of the list price on all books he bought in a six-month period and Victor paid a$15 fee to receive a 15% discount off of the list price on all books he bought in the same period. We''re told that EACH person bought books ...”
September 3, 2018
Rich.C@EMPOWERgmat.com posted a reply to Six children — A, B, C, D, E, and F — are going to sit i in the Problem Solving forum
“Hi All, We''re told that six children - A, B, C, D, E, and F - are going to sit in six chairs in a row, but Child E must be somewhere to the LEFT of Child F. We''re asked for the number of possible configurations of the children. This question is a permutation question with a small twist - and ...”
September 3, 2018
Brent@GMATPrepNow posted a reply to integers in the Problem Solving forum
“Here''s one way to look at it. Write all of the numbers as 3-digit numbers. That is, 000, 001, 002, 003, .... 998, 999 NOTE: Yes, I have started at 000 and ended at 999, even though though the question asks us to look at the numbers from 1 to 1000. HOWEVER, notice that 000 and 1000 do not ...”
September 1, 2018
Brent@GMATPrepNow posted a reply to How many positive integers less than 2*10^4 are there in in the Problem Solving forum
“In other words, "How many positive integers less than 20,000 are there in which each digit is a prime number?" The prime digits are: 2, 3, 5 and 7 Notice that, using the digits 2, 3, 5 and 7, we cannot create a 5-digit number that''s less than 20,000 So, we must consider 4 possible ...”
September 1, 2018
Brent@GMATPrepNow posted a reply to Each baseball team in a league has a roster of players in in the Problem Solving forum
“There are 2 pitchers for every 3 fielders So, out of every 5 players, there are 2 pitchers. So, in ONE 25-player team, there are 10 pitchers (and 15 fielders) So, if there are 12 teams, and there are 10 pitchers and 15 fielders per team, then... TOTAL number of pitchers = (12)(10 ) TOTAL ...”
September 1, 2018
Brent@GMATPrepNow posted a reply to Which of the following are/is prime? in the Problem Solving forum
“I. 143 143 = (11)(13) Since 143 is NOT prime, we can ELIMINATE C, D and E II. 147 Notice that 147 = 140 + 7 Since 140 is divisible by 7, and 7 is divisible by 7, we know that 147 is divisible by 7. Since 147 is NOT prime, we can ELIMINATE A So, the answer (by the process of elimination) ...”
September 1, 2018
Brent@GMATPrepNow posted a reply to A certain library assesses fines for overdue books as in the Problem Solving forum
“1st day - $0.10 2nd day -$0.20 or $0.40 (double or add$0.30) $0.20 is the lesser amount 3rd day -$0.40 or $0.50 (double or add$0.30) $0.40 is the lesser amount 4th day -$0.80 or $0.70 (double or add$0.30) $0.70 is the lesser amount The correct answer is B Cheers, Brent” August 31, 2018 Brent@GMATPrepNow posted a reply to The Hazelton coal-processing plant is a major employer in in the Critical Reasoning forum “PREMISE: Coal plant will be shut down it it doesn''t upgrade PREMISE: Expensive upgrade will force company to close, UNLESS it receives tax break PREMISE: To PREVENT increase in local unemployment, government may grant tax break IMPORTANT: the government''s goal is to PREVENT an increase in ...” August 30, 2018 Brent@GMATPrepNow posted a reply to Angela has 15 pairs of matched socks. If she loses 7 in the Problem Solving forum “We can also systematically eliminate 4 of the 5 answer choices. Let''s say the 15 PAIRS of socks are as follows: AA, BB, CC, DD, EE, FF, GG, HH, II, JJ, KK, LL, MM, NN, OO Let''s first see what happens if we "lose" 7 unmatched socks. Say, we lose, A, B, C, D, E, F, G We get: A, B, ...” August 30, 2018 Brent@GMATPrepNow posted a reply to What is the range of 10 numbers? in the Data Sufficiency forum “Target question: What is the range of 10 numbers? Statement 1: The average (arithmetic mean) of the 10 numbers is 10 Let''s TEST some values. There are several sets of numbers that satisfy statement 1. Here are two: Case a: the numbers are {10, 10, 10, 10, 10, 10, 10, 10, 10, 10}. In this ...” August 30, 2018 Brent@GMATPrepNow posted a reply to A jar contains 16 red balls and 8 white balls. If 3 balls ar in the Problem Solving forum “There are 24 balls in the jar (before any are removed) P(all 3 balls are white) = P(1st ball is white AND 2nd ball is white AND 3rd ball is white) = P(1st ball is white) x P(2nd ball is white) x P(3rd ball is white) = 8/24 x 7/23 x 6/22 = 1/3 x 7/23 x 3/11 = 7/253 ASIDE: rather than ...” August 30, 2018 Brent@GMATPrepNow posted a reply to Pumping alone at their respective constant rates, one inlet in the Problem Solving forum “Let''s assign a nice value to the volume of the tank. We want a volume that works well with the given information (1/2, 2/3, 3 hours and 6 hours). So, let''s say the tank has a total volume of 18 gallons One inlet pipe fills an empty tank to 1/2 of capacity in 3 hours 1/2 the tank is 9 ...” August 30, 2018 Brent@GMATPrepNow posted a reply to At a constant rate of flow, it take 20 minutes to fill a in the Problem Solving forum “Let''s assign a nice value to the volume of the pool. We want a volume that works well with the given information (20 minutes and 30 minutes). So, let''s say the pool has a total volume of 60 gallons It takes 20 minutes to fill a swimming pool with a LARGE hose In other words, the LARGE hose ...” August 30, 2018 Brent@GMATPrepNow posted a reply to If 4 is one solution of the equation x^2 + 3x + k = 10, in the Problem Solving forum “Let''s first determine the value of k. Since x = 4 is a solution to the equation x² + 3x + k = 10, we know that x = 4 SATISFIES the equation. That is: 4² + 3(4) + k = 10 Evaluate to get: 16 + 12 + k = 10 Solve for k to get: k = -18 So, the ORIGINAL equation is x² + 3x + (-18) = 10 ...” August 30, 2018 Brent@GMATPrepNow posted a reply to In a certain summer school program, there are five periods in the Problem Solving forum “Take the Science, and Science Lab classes and "glue" them together to get the super class "Science-Science-Lab" This ensures that Science Lab immediately follows the Science class So, we now have only 4 classes: English, Math, History and Science-Science-Lab We can arrange ...” August 29, 2018 Brent@GMATPrepNow posted a reply to Is the measure of one of the interior angles of in the Data Sufficiency forum “Target question: Is the measure of one of the interior angles of quadrilateral ABCD equal to 60? Key concept: the 4 angles in a quadrilateral must add to 360 degrees Statement 1: Two of the interior angles of ABCD are right angles. Let''s test some possible cases. There are infinitely ...” August 28, 2018 Brent@GMATPrepNow posted a reply to Solution X, which is 50% alcohol, is combined with solution in the Problem Solving forum “When solving mixture questions, I find it useful to sketch the solutions with the ingredients SEPARATED: https://i.imgur.com/X6UPop8.png Since we want to determine the volume of solution Y needed, let''s... ...let y = volume (in liters) of solution Y needed This means 16 - y = volume (in ...” August 28, 2018 Brent@GMATPrepNow posted a reply to Is xy>0? in the Data Sufficiency forum “Target question: Is xy>0? Statement 1: x + y > 0 This statement doesn''t FEEL sufficient, so I''ll TEST some values. There are several values of x and y that satisfy statement 1. Here are two: Case a: x = 1 and y = 1. In this case, xy = (1)(1) = 1. So, the answer to the target ...” August 28, 2018 Brent@GMATPrepNow posted a reply to When traveling at a constant speed of 32 miles per hour, a in the Problem Solving forum “Let''s see what happens after ONE HOUR of traveling. In ONE hour, the boat will travel 32 miles and will use 24 gallons of fuel So, the fuel consumption rate is 32 miles per 24 gallons Or we can write: fuel consumption rate = 32/24 miles/gallon 32/24 = 4/3 So, the fuel consumption rate = ...” August 28, 2018 Brent@GMATPrepNow posted a reply to Exactly 8 years ago, Jim's son was twice as old as Jim's in the Problem Solving forum “Jim’s son is now 5 years older than his daughter Let D = the daughter''s age NOW So D + 5 = the son''s age NOW This also means that D - 8 = the daughter''s age EIGHT YEARS AGO This also means that D + 5 - 8 = the son''s age EIGHT YEARS AGO Or we can say, D - 3 = the son''s age EIGHT YEARS ...” August 28, 2018 Brent@GMATPrepNow posted a reply to What is the sum of all multiples of 3 between 1 and 200? in the Problem Solving forum “Useful formula: 1 + 2 + 3 + 4 + . . . n = (n)(n + 1)/2 We want to find the sum: 3 + 6 + 9 + 12 + . . . 198 Factor out the 3 to get: 3(1 + 2 + 3 + 4 + . . . 66) Apply formula to get: 3(66)(67)/2 Evaluate to get: 6633 Answer: C Cheers, Brent” August 28, 2018 Rich.C@EMPOWERgmat.com posted a reply to When traveling at a constant speed of 32 miles per hour, a in the Problem Solving forum “Hi All, We''re told that when traveling at a constant speed of 32 miles per HOUR, a certain motorboat consumes 24 gallons of fuel per HOUR. We''re asked for the fuel consumption of this boat at this speed measured in miles traveled per gallon of fuel. Sometimes the big ''step'' you have to ...” August 28, 2018 Rich.C@EMPOWERgmat.com posted a reply to If x, y, and z are negative numbers such that z = 40x + 80y in the Data Sufficiency forum “Hi All, We''re told that X, Y and Z are NEGATIVE numbers such that Z = 40X + 80Y and X+Y = -1. We''re asked if Z is LESS than -60. This is a YES/NO question and can be solved by TESTing VALUES and/or using a bit of logic. To start, this question has some interesting limitations to it. Since ...” August 28, 2018 Rich.C@EMPOWERgmat.com posted a reply to The temperature of a place at noon on a certain day is 25% in the Data Sufficiency forum “Hi All, We''re told that the temperature of a place at noon on a certain day is 25% higher than the temperature of the same place at midnight on the same day. We''re asked for the temperature of the place at midnight. This question can be solved in a couple of different ways, but it''s actually ...” August 28, 2018 Brent@GMATPrepNow posted a reply to What is the value of x? in the Data Sufficiency forum “Here''s another way to look at it..... (1) 310x + 562y = 909 We can think of this as the equation of a line. The x- and y-coordinates of all points on the line will satisfy the equation 310x + 562y = 909 Since there are infinitely many points on the line, there are infinitely many possible ...” August 27, 2018 Brent@GMATPrepNow posted a reply to George bought a large electronic item with a 15% off coupon, in the Problem Solving forum “George was SUPPOSED to receive a 15% discount, but he received a 30% discount. So, he should have returned 15% of the original cost. However, the manager asked for half that amount (i.e., 7.5% of the original cost) In other words, 7.5% of the original cost =$40.50 IMPORTANT: at this point, ...”
August 27, 2018
Brent@GMATPrepNow posted a reply to GMAT Prep Problem 3 in the Problem Solving forum
“Here''s the complete question: Let''s first determine the least possible integer. We''ll use the answer choices to help us along... A) Could the smallest value on the card be 3? Well, the next larger integer is 4, and 3 x 4 = 12, which is OUTSIDE the given range of 15 to 200 So, we ...”
August 27, 2018
Brent@GMATPrepNow posted a reply to GMAT Prep Problem 1 in the Problem Solving forum
“Here''s another algebraic approach. Let M = Alice''s monthly take home pay Let f = the fraction we''ll use to calculate monthly savings The means that fM = the amount of \$ Alice saves each month. And this means that her annual savings = 12fM Important: If f = the fraction used to ...”
August 27, 2018
Brent@GMATPrepNow posted a reply to If m and n are integers greater than 1, is m^n>500? in the Data Sufficiency forum
“Target question: Is m^n > 500? Given: m and n are integers greater than 1 Statement 1: n > 8 We''re told that m and n are integers greater than 1 So, the SMALLEST possible value of m is 2 And, if n > 8, the SMALLEST possible value of n is 9 When we plug in these SMALLEST ...”
August 27, 2018
Brent@GMATPrepNow posted a reply to If x and y are positive integers and xy=36, what is the smal in the Problem Solving forum
“Since there aren''t many PAIRS of integers that have a product of 36, we can simply list the possibilities: x = 1 and y = 36. Here, the SUM = 37 x = 2 and y = 18. Here, the SUM = 20 x = 3 and y = 12. Here, the SUM = 15 x = 4 and y = 9. Here, the SUM = 13 x = 6 and y = 6. Here, the SUM = 12 ...”
August 27, 2018
Brent@GMATPrepNow posted a reply to For which of the following functions is f(a+b) = F(a) + f(b) in the Problem Solving forum
“One approach is to plug in numbers. Let''s let a = 1 and b = 1 So, the question becomes, "Which of the following functions are such that f(1+1) = f(1) + f(1)?" In other words, for which function does f(2) = f(1) + f(1)? A) If f(x)=x², does f(2) = f(1) + f(1)? Plug in to get: 2² ...”
August 27, 2018