prafulladhakate

prafulladhakate

Brent@GMATPrepNow posted a reply to Is it true that x > 0? in the Data Sufficiency forum
“Target question: Is it true that x > 0? Statement 1: x² = 2x Rewrite as: x² - 2x = 0 Factor: x(x - 2) = 0 So, EITHER x = 0 OR x = 2 Let''s examine each possible case Case a: If x = 0, then the answer to the target question is NO, it is not true that x > 0 Case b: If x = 2, then ...”
Yesterday
Rich.C@EMPOWERgmat.com posted a reply to In a certain bathtub, both the hot and cold water fixtures in the Problem Solving forum
“Hi All, We''re told that In a certain bathtub, both the hot and cold water fixtures leak. The cold water leak alone would fill an empty bucket in C hours, and the hot water leak alone will fill the same bucket in H hours, where C < H. If both fixtures began to leak at the same time into the ...”
March 23, 2019
Brent@GMATPrepNow posted a reply to Problem with a practice question in the GMAT Math forum
“Here''s my full solution: https://www.beatthegmat.com/for-all-positive-integers-m-t299496.html Cheers, Brent”
March 23, 2019
ceilidh.erickson posted a reply to If a car traveled from Townsend to Smallville at an average in the Data Sufficiency forum
“Average speed is a WEIGHTED average: (total distance)/(total time). Since we''re given that this is a round trip, the distance of each leg of the trip will be the same. Since we know the average speed for one leg of the trip, all we need to know to calculate the overall average speed is the ...”
March 22, 2019
ceilidh.erickson posted a reply to Of the 800 sweaters in a certain store, 150 are red. How in the Data Sufficiency forum
“Overlapping Sets are a common question type on the GMAT, and the double-set matrix is often the easiest way to solve. For more on how to use the matrix, see: https://www.beatthegmat.com/at-a-charity-fundraiser-180-of-the-guests-had-a-house-both-t307024.html#828495 ...”
March 22, 2019
Rich.C@EMPOWERgmat.com posted a reply to If \(xy \neq 0\), and 75 percent of \(x\) equals 125 percent in the Problem Solving forum
“Hi All, We''re told that neither X nor Y can equal 0 and that 75% of X is equal to 125% of Y. We''re asked which of the following is true. This question can be solved in a couple of different ways, including by TESTing VALUES. IF.... X = 100, then (75% of X) = 75 75 = 125% of Y 75 = ...”
March 22, 2019
Rich.C@EMPOWERgmat.com posted a reply to If \(xy \neq 0\) and \(2x + 3y\) is equal to 175 percent in the Problem Solving forum
“Hi All, We''re told that neither X nor Y can be 0 and that (2X + 3Y) is 175% of 8X. We''re asked for the value of X/Y. This question can be solved in a number of different ways, including by TESTing THE ANSWERS. Between Answers B and D, Answer D would be an easier Answer to TEST, so let''s try ...”
March 22, 2019
ceilidh.erickson posted a reply to Of the 800 sweaters in a certain store, 150 are red. How in the Data Sufficiency forum
“We can represent this problem as an OVERLAPPING SETS problem: red v. not red, wool v. not wool: https://i.postimg.cc/CBMcFwJt/Screenshot-2019-03-22-15-56-23.png Of the 800 sweaters in a certain store, 150 are red. How many of the red sweaters at the store are made of pure wool? We can also ...”
March 22, 2019
Rich.C@EMPOWERgmat.com posted a reply to Find the range of values of \(x\) that satisfy the in the Problem Solving forum
“Hi All, We''re asked for the range of values of X that satisfy the inequality (X+1)(X-2) > 4. This question can be approached in a couple of different ways, including by TESTing VALUES. IF... X=10, then (11)(8) = 88 which is greater than 4. Thus, X=10 is a possible solution. Eliminate ...”
March 22, 2019
ceilidh.erickson posted a reply to Mauritius was a British colony for almost 200 years, in the Sentence Correction forum
“In this sentence, we have 2 independent clauses in the non-underlined portions: 1. "Mauritius was a British colony" 2. "the English language was never really spoken" In the original sentence, these clauses are joined only with a comma. This is what we call a comma splice or ...”
March 22, 2019
ceilidh.erickson posted a reply to Hunter: Many people blame hunters alone for the decline in in the Critical Reasoning forum
“The main thrust of this hunter''s argument is that black bears have also played an important role in the decline of the deer population. The evidence given for this argument: - the forest''s protected black bear population has risen sharply - examination of black bears found dead in the forest ...”
March 22, 2019
Brent@GMATPrepNow posted a reply to If \(xy \neq 0\), and 75 percent of \(x\) equals 125 percent in the Problem Solving forum
“GIVEN: 75 percent of x equals 125 percent of y Rewrite as: 3/4 of x = 5/4 of y Or we can say: (3/4)(x) = (5/4)( y) Multiply both sides by 4 to get: 3x = 5y Divide both sides by 5 to get: 3x/5 = y Rewrite as: y = (3/5)(x) Or y = 3/5 of x Or y = 60/100 of x Or y = 60% of x Answer: C ...”
March 22, 2019
Brent@GMATPrepNow posted a reply to If m and n are prime numbers, what is the value of m+n? in the Data Sufficiency forum
“ Given: m and n are prime numbers Target question: What is the value of m+n? Statement 1: 15 ≤ m < n ≤ 20 17 and 19 are the only PRIME numbers from 15 to 20 inclusive So, it must be the case that m = 17 and n = 19 So, the answer to the target question is m+n = 17 + 19 = 33 Since ...”
March 22, 2019
ceilidh.erickson posted a reply to Wind farms, which generate electricity using arrays of in the Critical Reasoning forum
“The logical flaw in this argument falls under the category of what I like to call MIXED METRICS: it seems like the premises and conclusion are talking about the same statistic, but in fact we''re looking at different mathematical or categorical ideas. Any time you see one statistic / metric / ...”
March 22, 2019
ceilidh.erickson posted a reply to Wind farms, which generate electricity using arrays of in the Critical Reasoning forum
“When WEAKENING an argument, you must first find the LOGICAL FLAW: the missing assumption that would be needed to connect premises to conclusion. Premises: - Wind farms require vast expanses of open land. - County X and County Y have similar terrain - the population density of County X is ...”
March 22, 2019
ceilidh.erickson posted a reply to At a charity fundraiser, 180 of the guests had a house both in the Data Sufficiency forum
“Overlapping Sets are a common question type on the GMAT, and the double-set matrix is often the easiest way to solve. For more on how to use the matrix, see: https://www.beatthegmat.com/among-the-members-of-the-malmo-family-there-are-three-times-t306786.html#827756 ...”
March 22, 2019
ceilidh.erickson posted a reply to At a charity fundraiser, 180 of the guests had a house both in the Data Sufficiency forum
“This is a classic OVERLAPPING SETS problem. It is usually best to set these up with a DOUBLE-SET MATRIX: https://i.postimg.cc/XpkxyS5g/Screenshot-2019-03-22-14-31-06.png From the question stem, we know that 180 guests have houses in both locations, and we''re looking for the ratio of the two ...”
March 22, 2019
Brent@GMATPrepNow posted a reply to If n is an integer, is n + 1 odd? in the Data Sufficiency forum
“Target question: Is n + 1 odd? Some important rules: #1. ODD +/- ODD = EVEN #2. ODD +/- EVEN = ODD #3. EVEN +/- EVEN = EVEN Statement 1: n + 2 is an even integer. In other words: n + EVEN = EVEN In other words: n = EVEN - EVEN By Rule #3, n must be even, which means n+1 is ODD The ...”
March 22, 2019
Brent@GMATPrepNow posted a reply to Express 2^20-2^19-2^18-2^17 as a power of 2. in the Problem Solving forum
“2^20 - 2^19 - 2^18 - 2^17 = 2^17(2^3 - 2^2 - 2^1 - 1) = 2^17(8 - 4 - 2 - 1) = 2^17(1) = 2^17 Answer: C Cheers, Brent”
March 22, 2019
Max@Math Revolution posted a new topic called Express 2^20-2^19-2^18-2^17 as a power of 2. in the Problem Solving forum
“[GMAT math practice question] Express 2^20-2^19-2^18-2^17 as a power of 2. A. 2^15 B. 2^16 C. 2^17 D. 2^18 E. 2^19”
March 22, 2019
Max@Math Revolution posted a reply to Jeonghee has 5 different red cards and 5 different blue card in the Problem Solving forum
“=> The total number of ways in which 5 cards can be chosen out of 10 cards is 10P5 = 10*9*8*7*6. There are 5*4*3*2*1 arrangements of each of BBBBB and RRRRR. There are 5*4*3*2*5 arrangements of each of BBBBR, RBBBB, RRRRB and BRRRR. There are 5*4*3*5*4 arrangements of each of BBBRR, ...”
March 22, 2019
Max@Math Revolution posted a new topic called If m and n are prime numbers, what is the value of m+n? in the Data Sufficiency forum
“[GMAT math practice question] If m and n are prime numbers, what is the value of m+n? 1) 15 ≤ m < n ≤ 20 2) mn = 323”
March 22, 2019
Max@Math Revolution posted a reply to Is n an odd number? in the Data Sufficiency forum
“=> Forget conventional ways of solving math questions. For DS problems, the VA (Variable Approach) method is the quickest and easiest way to find the answer without actually solving the problem. Remember that equal numbers of variables and independent equations ensure a solution. The first ...”
March 22, 2019
Brent@GMATPrepNow posted a reply to What is the total cost to make 7 long distance telephone in the Data Sufficiency forum
“Target question: What is the total cost to make 7 long distance telephone calls? When we SCAN the statements, we see the key phrase: at least This allows us to jump straight to... Statements 1 and 2 combined There are infinitely many scenarios that satisfy BOTH statements. Here are two: ...”
March 21, 2019
Brent@GMATPrepNow posted a reply to Skier Lindsey Vonn completes a straight 300-meter downhill in the Problem Solving forum
“The ride up the mountain took 135 seconds longer than her run down the mountain Start with a word equation: (time going UP mountain) = (time going DOWN mountain) + 135 time = distance/speed We can now write: 300/(x - 8) = 300/(x + 10) + 135 Multiply both sides by (x - 8) to get: 300 = 300(x - ...”
March 21, 2019
Max@Math Revolution posted a new topic called What is the smallest positive integer n such that n / 420 ca in the Problem Solving forum
“[GMAT math practice question] What is the smallest positive integer n such that n / 420 can be expressed as a terminating decimal? A. 18 B. 21 C. 24 D. 30 E. 42”
March 21, 2019
Max@Math Revolution posted a reply to The number 1000 lies between two consecutive perfect squares in the Problem Solving forum
“=> 31^2 = 961 32^2 = 1024 1024 is the perfect square closest to 1000. Therefore, D is the answer. Answer: D”
March 21, 2019
Max@Math Revolution posted a new topic called If m and n are positive integers, is m+n divisible by 15? in the Data Sufficiency forum
“[GMAT math practice question] If m and n are positive integers, is m+n divisible by 15? 1) m is divisible by 9 and n is divisible by 15. 2) mn is divisible by 225.”
March 21, 2019
Max@Math Revolution posted a reply to xy=? in the Data Sufficiency forum
“=> Forget conventional ways of solving math questions. For DS problems, the VA (Variable Approach) method is the quickest and easiest way to find the answer without actually solving the problem. Remember that equal numbers of variables and independent equations ensure a solution. The first ...”
March 21, 2019
Brent@GMATPrepNow posted a reply to x is the product of all even numbers from 2 to 50, inclusive in the Problem Solving forum
“x = (2)(4)(6)....(46)(48)(50) = (1)(2)(2)(2)(3)(2).....(23)(2)(24)(2)(25)(2) Notice that: x is divisible by 2. This tells us that x+1 is 1 greater than a multiple of 2. In other words, x+1 is NOT divisible by 2 x is divisible by 3. This tells us that x+1 is 1 greater than a multiple of 3. ...”
March 20, 2019
Rich.C@EMPOWERgmat.com posted a reply to x is the product of all even numbers from 2 to 50, inclusive in the Problem Solving forum
“Hi All, We''re told that X is the product of all even numbers from 2 to 50, inclusive. We''re asked to define what the smallest prime factor of (X+1) must be. This particular question is a variation on an Official question that periodically pops up in the forums. The main idea behind this prompt ...”
March 20, 2019
Brent@GMATPrepNow posted a reply to If there are 4 pairs of twins, and a committee will be in the Problem Solving forum
“Here''s one approach. Take the task of selecting the 3 committee members and break it into stages. Stage 1: Select the 3 twins from which we will select 1 spouse each. There are 4 sets of twins, and we must select 3 of them. Since the order in which we select the 3 twins does not matter, ...”
March 20, 2019
Brent@GMATPrepNow posted a reply to If arc PQR above is a semicircle, what is the length of diam in the Data Sufficiency forum
“http://s16.postimg.cc/p2mwbwdpt/triangle_PQR.jpg We can answer this question without performing any calculations. Instead, we can use some visualization. Important point: For geometry DS questions, we are typically checking to see whether the statements "lock" a particular angle or ...”
March 20, 2019
Max@Math Revolution posted a new topic called Jeonghee has 5 different red cards and 5 different blue card in the Problem Solving forum
“[GMAT math practice question] Jeonghee has 5 different red cards and 5 different blue cards. She shuffles the10 cards, and then places 5 of the cards in a row. What is the probability that all red cards are adjacent to each other and all blue cards are adjacent to each other in her row? A. 2/5 ...”
March 20, 2019
Max@Math Revolution posted a reply to A box contains 3 red balls, 4 green balls, 5 yellow balls, 6 in the Problem Solving forum
“=> The maximum number of draws we can make without drawing 5 balls of a single color is 3 + 4 + 4 + 4 + 4 = 14. This occurs when we draw 3 red balls, 4 green balls, 4 yellow balls, 4 blue balls and 4 white balls. If we draw one more ball, then we will have drawn 5 balls of a single color. ...”
March 20, 2019
Max@Math Revolution posted a new topic called Is n an odd number? in the Data Sufficiency forum
“[GMAT math practice question] Is n an odd number? 1) n and n+2 are prime numbers 2) n+5 is a multiple of 5”
March 20, 2019
Max@Math Revolution posted a reply to Is √15n an integer? in the Data Sufficiency forum
“=> Forget conventional ways of solving math questions. For DS problems, the VA (Variable Approach) method is the quickest and easiest way to find the answer without actually solving the problem. Remember that equal numbers of variables and independent equations ensure a solution. Since we ...”
March 20, 2019
Max@Math Revolution posted a new topic called [Math Revolution] Practice “Math Questions of the Day” in the GMAT Math forum
“To help you sharpen your math skills and hit your target score of Q49-51, we are sending you 4 math questions (2 DS, 2 PS) and solutions regularly. These questions are the types of questions appearing in GMAT exam frequently. Please Click the link for solutions. ...”
March 20, 2019
Rich.C@EMPOWERgmat.com posted a reply to A furniture store sells only two models of desks, model A in the Problem Solving forum
“Hi All, We''re told that a furniture store sells only two models of desks, model A and model B. The selling price of model A is $120, which is 30 percent of the selling price of the model B - and the furniture store sells 2,000 desks, 3/4 of which are model B. We''re asked for the TOTAL revenue ...”
March 20, 2019
Brent@GMATPrepNow posted a reply to In a group of children, the average (arithmetic mean) weight in the Problem Solving forum
“We can also use weighted averages to solve this Weighted average of groups combined = (group A proportion)(group A average) + (group B proportion)(group B average) + (group C proportion)(group C average) + ... Let G = number of girls Let B = number of boys So, G+B = TOTAL number of children ...”
March 20, 2019
Rich.C@EMPOWERgmat.com posted a reply to Point A in the xy-coordinate system is shown below. Given in the Problem Solving forum
“Hi All, We''re told that Point A is in the xy-coordinate system as shown - and that two other points B (4a, b) and C (2a, 5b) are also in the system. We''re asked for the AREA of triangle ABC in terms of a and b. This question can be approached in a couple of different ways, including by TESTing ...”
March 20, 2019
Rich.C@EMPOWERgmat.com posted a reply to In a group of children, the average (arithmetic mean) weight in the Problem Solving forum
“Hi All, We''re told that in a group of children, the average (arithmetic mean) weight of the boys is 60 pounds, the average weight of the girls is 48 pounds and the average weight of ALL of the children in the group is 50 pounds. We''re asked for the ratio of the number of boys to the number of ...”
March 20, 2019
Brent@GMATPrepNow posted a reply to If the average (arithmetic mean) of five consecutive negativ in the Problem Solving forum
“Let x = the 1st (smallest integer) So, x+1 = the 2nd integer x+2 = the 3rd integer x+3 = the 4th integer x+4 = the 5th integer (greatest integer) What is the difference between the greatest and least of the five integers? Difference = ( x+4) - x = 4 Answer: A Cheers, Brent”
March 19, 2019
Brent@GMATPrepNow posted a reply to The number 1000 lies between two consecutive perfect squares in the Problem Solving forum
“Let''s examine some perfect squares that are close to 1000 30² = 900 31² = 961 32² = 1024 So, 1000 lies between 961 (aka 31²) and 1024 (aka 32²) 1000 is closer to 1024 (aka 32²) than to 961 Answer: D Cheers, Brent”
March 19, 2019
Max@Math Revolution posted a new topic called The number 1000 lies between two consecutive perfect squares in the Problem Solving forum
“[GMAT math practice question] The number 1000 lies between two consecutive perfect squares. Which one of these square integers is closest to 1000? A. 29^2 B. 30^2 C. 31^2 D. 32^2 E. 33^2”
March 19, 2019
Max@Math Revolution posted a new topic called xy=? in the Data Sufficiency forum
“[GMAT math practice question] xy=? 1) (x-2)^2 = -|y-3| 2) |x-2| +√( y-3) =0”
March 19, 2019
Brent@GMATPrepNow posted a reply to Danny spends $360 buying his favorite dolls. If he buy only in the Problem Solving forum
“Let L = cost of 1 LARGE LemonHead doll So L-1 = cost of 1 SMALL LemonHead doll If he buys only small LemonHead dolls, which are $1 cheaper than the large LemonHead dolls, he could buy 5 more dolls than if he were to buy only large LemonHead dolls. Let''s first write a "word equation": ...”
March 18, 2019
Max@Math Revolution posted a new topic called A box contains 3 red balls, 4 green balls, 5 yellow balls, 6 in the Problem Solving forum
“[GMAT math practice question] A box contains 3 red balls, 4 green balls, 5 yellow balls, 6 blue balls and 7 white balls. What is the minimum number of balls that must be drawn from the box without replacement to guarantee that at least 5 balls of a single color will be drawn? A. 10 ...”
March 18, 2019
Max@Math Revolution posted a new topic called Is √15n an integer? in the Data Sufficiency forum
“[GMAT math practice question] 3.18 Is $$\sqrt{15n}$$ an integer? 1) n is a multiple of 3 2) n is the square of an integer”
March 18, 2019
Max@Math Revolution posted a reply to What is the value of 2(1-1/2) + 3(1-1/3) + … + 100(1 – 1 in the Problem Solving forum
“=> Note: This sum has 100 – 2 + 1 = 99 terms. 2(1-1/2) + 3(1-1/3) + … + 100(1 – 1/100) = (2 – 1) + (3 - 1) + … + (100 – 1) = 2 + 3 + … + 100 – ( 1 + 1 + … + 1 ) = ( 2 + 100 )99 / 2 – 99 = 51*99 – 99 = (51-1)*99 = 50*99 = 4950 Therefore, the answer is C. ...”
March 18, 2019
Max@Math Revolution posted a reply to If √x+√y=7 and √x-√y=5, what is the value of xy? in the Problem Solving forum
“=> Adding the two equations yields 2√x = 12, so x = 36. Subtracting the two equations yields 2√y = 2, so y = 1. Therefore, xy = 36. Therefore, the answer is C. Answer: C”
March 18, 2019
Max@Math Revolution posted a reply to The point (p,q) lies in which quadrant of the x-y plane? in the Data Sufficiency forum
“=> Forget conventional ways of solving math questions. For DS problems, the VA (Variable Approach) method is the quickest and easiest way to find the answer without actually solving the problem. Remember that equal numbers of variables and independent equations ensure a solution. The first ...”
March 18, 2019
Max@Math Revolution posted a reply to If f(x)=ax^2+bx+c, where a, b and c are integers, is b=0? in the Data Sufficiency forum
“=> Forget conventional ways of solving math questions. For DS problems, the VA (Variable Approach) method is the quickest and easiest way to find the answer without actually solving the problem. Remember that equal numbers of variables and independent equations ensure a solution. The first ...”
March 18, 2019
Brent@GMATPrepNow posted a reply to Bea owns how many more CDs than Al owns? (1) If Bea gives 9 in the Data Sufficiency forum
“Let A = number of CDs Al owns Let B = number of CDs Bea owns Target question: What is the value of B - A? Statement 1: If Bea gives 9 of her CDs to Al, then Al will own twice as many CDs as Bea owns. We can create the equation: 2(B - 9) = A+9 Expand left side to get 2B - 18 = A+9 ...”
March 16, 2019
Brent@GMATPrepNow posted a reply to How many different 3-digit numbers are greater than 299 and in the Problem Solving forum
“Take the task of creating the 3-digit numbers and break it into stages. Stage 1: Select the first digit (hundreds digit) Since the first digit can be 3, 4, 5, 7 or 9, we can complete stage 1 in 5 ways Stage 2: Select the second digit (tens digit) Since the second digit can be 0, 2, 3, 4, ...”
March 15, 2019
Rich.C@EMPOWERgmat.com posted a reply to A certain hotel has 1,400 single rooms and 420 double rooms. in the Problem Solving forum
“Hi camitava, This is essentially a rate question. Here''s how to solve it: Single rooms take one person 15 minutes to clean and double rooms take one person 20 minutes to clean. 15 mins. = 1/4 hour 20 mins. = 1/3 hour With 1400 single rooms x 1/4 hour = 350 hours of total work for ...”
March 15, 2019
Rich.C@EMPOWERgmat.com posted a reply to A cosmetics company would like to market a six-item gift in the Problem Solving forum
“Hi All, We''re told that a cosmetics company would like to market a 6-item gift basket bundle from a set of 10 possible items, but 49 of the potential bundles have already been eliminated from consideration. We''re asked for the total number of potential bundles that are still being considered. ...”
March 15, 2019
Rich.C@EMPOWERgmat.com posted a reply to What is the sum of the integers from 1 to 999, inclusive? A in the Problem Solving forum
“Hi All, We''re asked for the sum of the integers from 1 to 999, inclusive. This question can be approached in a number of different ways, including by "bunching" The sum of 1 and 999 is 1,000 The sum of 2 and 998 is 1,000 The sum of 3 and 997 is 1,000 Etc. Using the numbers ...”
March 15, 2019
Rich.C@EMPOWERgmat.com posted a reply to A basketball team’s current roster consists of g guards an in the Problem Solving forum
“Hi All, We''re told that a basketball team’s current roster consists of G guards and F forwards - and 2 guards join and 1 forward leaves. We''re asked for the probability that a player chosen at random is a guard. This question can be approached in a couple of different ways, including by ...”
March 15, 2019
Brent@GMATPrepNow posted a reply to The cost of delivery for an order of desk chairs was $10.00 in the Data Sufficiency forum
“Target question: Is n > 24? Given: The cost of delivery for an order of desk chairs was $10.00 for the 1st chair, and $1 for each additional chair in the order. The office manager placed an order for n desk chairs. Statement 1: The delivery cost for the order totaled more than $30.00 ...”
March 15, 2019
Brent@GMATPrepNow posted a reply to What is the average (arithmetic mean) of eleven consecutive in the Data Sufficiency forum
“There''s a nice rule that says, "In a set where the numbers are equally spaced, the mean will equal the median." Since the consecutive integers are equally-spaced, their mean and median will be equal. Target question: What is the average of eleven consecutive integers? ...”
March 15, 2019
Max@Math Revolution posted a new topic called What is the value of 2(1-1/2) + 3(1-1/3) + … + 100(1 – 1/100 in the Problem Solving forum
“[GMAT math practice question] What is the value of 2(1-1/2) + 3(1-1/3) + … + 100(1 – 1/100)? A. 3600 B. 4800 C. 4950 D. 5000 E. 5050”
March 15, 2019
Max@Math Revolution posted a reply to If n, n/3 and n/4 are positive integers, and n is less than in the Problem Solving forum
“=> The condition n/3 is a positive integer tells us that n is a positive multiple of 3. The condition n/4 is a positive integer tells us that n is a positive multiple of 4. Thus, n is a positive multiple of 12. The number of positive multiples of 12 less than or equal to 100 is 8 since ...”
March 15, 2019
Max@Math Revolution posted a new topic called The point (p,q) lies in which quadrant of the x-y plane? in the Data Sufficiency forum
“[GMAT math practice question] The point (p,q) lies in which quadrant of the x-y plane? 1) (p+1, q) lies in the 2nd quadrant 2) (q-1, p) lies in the 4th quadrant”
March 15, 2019
Max@Math Revolution posted a reply to If xyz ≠ 0, is x^3y^4z^5 > 0? in the Data Sufficiency forum
“=> Forget conventional ways of solving math questions. For DS problems, the VA (Variable Approach) method is the quickest and easiest way to find the answer without actually solving the problem. Remember that equal numbers of variables and independent equations ensure a solution. The first ...”
March 15, 2019
Rich.C@EMPOWERgmat.com posted a reply to After multiplying a positive integer A, which has n digits, in the Problem Solving forum
“Hi Gmat_mission, We''re told that after multiplying a positive integer A (which has N digits) by (N+2), we get a number with (N+1) digits, all of whose DIGITS are (N+1). We''re asked for the number of possible values of A that ''fit'' this description. To start, this question certainly ...”
March 15, 2019
Rich.C@EMPOWERgmat.com posted a reply to At a certain supplier, a machine of type A costs $20,000 and in the Problem Solving forum
“Hi All, This question is really just about basic arithmetic and staying organized. Based on the information in the prompt, there are two ''total costs'' that we have to calculate... Total cost of purchasing 2 Type A machines = Base Price = (2)($20,000) = $40,000 The 20% down payment = ...”
March 15, 2019
Rich.C@EMPOWERgmat.com posted a reply to In an office of eleven people, everyone but Lauren each in the Problem Solving forum
“Hi All, We''re told that in an office of 11 people, everyone but Lauren each contributed D dollars to buy her a surprise gift for her birthday, but the gift cost a total of G dollars, which was an amount that was less than the total collected. We''re asked - if each member who donated is to ...”
March 15, 2019
Brent@GMATPrepNow posted a reply to If 320 people attended the wedding and 200 attendees drank in the Data Sufficiency forum
“This question is somewhat ambiguous, since it''s hard to say whether "nondrinkers" in statement 1 refers to people who drank neither beer nor wine, or did not drink beer. I''m assuming that it means to not drink beer, so I''ve add that to the question below. One approach is to use ...”
March 14, 2019
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 ...”
March 14, 2019
Max@Math Revolution posted a new topic called If √x+√y=7 and √x-√y=5, what is the value of xy? in the Problem Solving forum
“[GMAT math practice question] If √x+√y=7 and √x-√y=5, what is the value of xy? A. 16 B. 25 C. 36 D. 49 E. 64”
March 14, 2019
Max@Math Revolution posted a reply to Which of the following could be the number of diagonals of a in the Problem Solving forum
“=> The number of diagonals of an n-polygon is nC2 – n = n(n-1)/2 – n=n(n-3)/2. If n = 4, then the number of diagonals is 4C2 – 4 = 6 – 4 = 2. If n = 5, then the number of diagonals is 5C2 – 5 = 10 – 5 = 5. If n = 6, then the number of diagonals is 6C2 – 6 = 15 – 6 = 9. If n ...”
March 14, 2019
Max@Math Revolution posted a new topic called If f(x)=ax^2+bx+c, where a, b and c are integers, is b=0? in the Data Sufficiency forum
“[GMAT math practice question] If f(x)=ax^2+bx+c, where a, b and c are integers, is b=0? 1) f(49)=f(-49)=0 2) f(0)f(49)=0”
March 14, 2019
Max@Math Revolution posted a reply to If x and y are positive integers, x/y=? in the Data Sufficiency forum
“=> Forget conventional ways of solving math questions. For DS problems, the VA (Variable Approach) method is the quickest and easiest way to find the answer without actually solving the problem. Remember that equal numbers of variables and independent equations ensure a solution. The first ...”
March 14, 2019
Brent@GMATPrepNow posted a reply to combinations in the Problem Solving forum
“Sure thing. Number of outcomes that OBEY the restriction = (total # of outcomes that IGNORE the restriction) - (# of outcomes that BREAK the restriction) total # of outcomes that IGNORE the restriction Select any 3 people from the 8 people We can do this in 8C3 ways (= 56 ways) # of ...”
March 13, 2019
Brent@GMATPrepNow posted a reply to If when x is divided by z, the result is y remainder q, then in the Problem Solving forum
“When it comes to remainders, 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, then we ...”
March 13, 2019
Brent@GMATPrepNow posted a reply to If $5,000 invested for one year at p percent simple annual i in the Data Sufficiency forum
“The great thing about DS questions is that we aren''t required to perform calculations if we know that we COULD perform those calculations. Here''s what I mean: Target question: What amount must be invested at k percent simple annual interest for one year to yield the same amount of dollars ? ...”
March 13, 2019
Brent@GMATPrepNow posted a reply to If xyz ≠ 0, is x^3y^4z^5 > 0? in the Data Sufficiency forum
“ Given: xyz ≠ 0 Target question: Is x³y⁴z⁵ > 0? This is a great candidate for rephrasing the target question. Since we know that x² must be POSITIVE, we can safely take the inequality x³y⁴z⁵ > 0 and divide both sides by x² to get: xy⁴z⁵ > 0 Similarly, since ...”
March 13, 2019
Brent@GMATPrepNow posted a reply to Set M is composed of the positive even integers up to 100. in the Problem Solving forum
“Set M is composed of the positive even integers up to 100. Set M = {2, 4, 6, 8, . . . . 96, 98, 100} Set N is composed of the odd integers from –1 to 99 Set N = {-1, 1, 3, 5, . . . 95, 97, 99} What is the value of (the sum of Set M) – (the sum of Set N)? SUM of set M = 2 + 4 + 6 + 8 + ...”
March 13, 2019
Brent@GMATPrepNow posted a reply to A certain ball was dropped from a window 8 meters above a in the Problem Solving forum
“Drop 8 meters Rise 4 meters Drop 4 meters Rise 2 meters Drop 2 meters Rise 1 meters (DONE!) 8 + 4 + 4 + 2 + 2 + 1 = 21 meters Answer: A Cheers, Brent”
March 13, 2019
Brent@GMATPrepNow posted a reply to A certain hotel has 1,400 single rooms and 420 double rooms. in the Problem Solving forum
“The hotel has 1,400 single rooms, and one person can clean a single room every 15 minutes So, one person can clean 4 single rooms in ONE HOUR In other words, it takes 1 WORKER HOUR to clean 4 single rooms 1400/4 = 350 So, it takes 350 WORKER HOURS to clean 1400 rooms The hotel has 420 ...”
March 13, 2019
Brent@GMATPrepNow posted a reply to The number of candidates rejected in a certain admission pro in the Problem Solving forum
“The number of candidates rejected in a certain admission process was four times GREATER than the number of candidates accepted. Let x = the number of candidates accepted So, x + 4x = the number of candidates rejected In other words, 5x = the number of candidates rejected So, 6x = TOTAL number ...”
March 13, 2019
Max@Math Revolution posted a new topic called If n, n/3 and n/4 are positive integers, and n is less than in the Problem Solving forum
“[GMAT math practice question] If n, n/3 and n/4 are positive integers, and n is less than or equal to 100, how many values of n are possible? A. 6 B. 7 C. 8 D. 9 E. 10”
March 13, 2019
Max@Math Revolution posted a reply to Alice, Bob, Cindy, Darren, Eddie, Fabian sit on six chairs a in the Problem Solving forum
“=> Note: Because the table is round, Alice’s choice of chair does not change the number of possible arrangements. Once Alice is seated, Bob’s position is determined. Cindy has 4 remaining possible seats. Cindy’s choice determines Darren’s position. Eddie then has 2 remaining ...”
March 13, 2019
Max@Math Revolution posted a new topic called If xyz ≠ 0, is x^3y^4z^5 > 0? in the Data Sufficiency forum
“[GMAT math practice question] If xyz ≠ 0, is x^3y^4z^5 > 0? 1) xz > 0 2) xyz > 0”
March 13, 2019
Max@Math Revolution posted a reply to x and y are integers. If y ≠ 3, is x = 4? in the Data Sufficiency forum
“=> Forget conventional ways of solving math questions. For DS problems, the VA (Variable Approach) method is the quickest and easiest way to find the answer without actually solving the problem. Remember that equal numbers of variables and independent equations ensure a solution. Since we ...”
March 13, 2019
Max@Math Revolution posted a new topic called [Math Revolution] Practice “Math Questions of the Day” in the GMAT Math forum
“To help you sharpen your math skills and hit your target score of Q49-51, we are sending you 4 math questions (2 DS, 2 PS) and solutions regularly. These questions are the types of questions appearing in GMAT exam frequently. Please Click the link for solutions. ...”
March 13, 2019
Rich.C@EMPOWERgmat.com posted a reply to A student worked 20 days. For each of the amount shown in th in the Problem Solving forum
“Hi All, We''re told that a student worked 20 days - and the given table shows the number of days that the student earned each of 5 possible amounts of money. We''re asked for the MEDIAN amount of money earned per day for those 20 days. Since there are 20 total days, the MEDIAN will be the ...”
March 12, 2019
Rich.C@EMPOWERgmat.com posted a reply to In a group of 24 musicians, some are pianists and the rest a in the Problem Solving forum
“Hi All, We''re told that in a group of 24 musicians, some are pianists and the rest are violinists and exactly 1/2 of the pianists and exactly 2/3 of the violinists belong to a union. We''re asked for the LEAST possible number of union members in the group. This question can be approached in a ...”
March 12, 2019
Brent@GMATPrepNow posted a reply to In a group of 24 musicians, some are pianists and the rest a in the Problem Solving forum
“In a group of 24 musicians, some are pianists and the rest are violinists. Let x = number of pianists So, 24-x = number of violinists Exactly 1/2 of the pianists and exactly 2/3 of the violinists belong to a union. So, the number of pianists in the union = x/2 And the number of violinists in ...”
March 12, 2019
Max@Math Revolution posted a new topic called Which of the following could be the number of diagonals of a in the Problem Solving forum
“[GMAT math practice question] Which of the following could be the number of diagonals of an n-polygon? A. 3 B. 6 C. 8 D. 12 E. 20”
March 12, 2019
Max@Math Revolution posted a new topic called If x and y are positive integers, x/y=? in the Data Sufficiency forum
“[GMAT math practice question] If x and y are positive integers, x/y=? 1) 2^{x+y}3^{xy}=72 2) 2^x3^y=12”
March 12, 2019
Max@Math Revolution posted a new topic called Alice, Bob, Cindy, Darren, Eddie, Fabian sit on six chairs a in the Problem Solving forum
“[GMAT math practice question] Alice, Bob, Cindy, Darren, Eddie, Fabian sit on six chairs around a large round table. Alice must sit opposite Bob and Cindy must sit opposite Darren. How many seating arrangements are possible? A. 6 B. 8 C. 24 D. 120 ...”
March 12, 2019
Max@Math Revolution posted a new topic called x and y are integers. If y ≠ 3, is x = 4? in the Data Sufficiency forum
“[GMAT math practice question] x and y are integers. If y ≠ 3, is x = 4? 1) x+y = 7 2) x^2+y^2 = 25”
March 12, 2019
Rich.C@EMPOWERgmat.com posted a reply to If a certain reel of film runs at 5/6 of a frame per second, in the Problem Solving forum
“Hi All, We''re told that a certain reel of film runs at 5/6 of a frame per second. We''re asked how long it will take to run 2580 frames of the film. While this question involves some ''ugly'' numbers, the answer choices are sufficiently ''spread out'' that you can use estimation to get the ...”
March 11, 2019
Rich.C@EMPOWERgmat.com posted a reply to Five friends play blackjack in Las Vegas and lose an average in the Problem Solving forum
“Hi All, We''re told that 5 friends play blackjack in Las Vegas and lose an AVERAGE of $100 each - with the losses of two of the friends totaling $380. We''re asked for the AVERAGE loss of the other 3 friends. This question is a standard Average Formula question and requires just a bit or ...”
March 11, 2019
Rich.C@EMPOWERgmat.com posted a reply to The R students in a class agree to contribute equally to buy in the Problem Solving forum
“Hi All, While this question is wordy, and will require some note-taking, it can be solved by TESTing VALUES. Let''s TEST... R = 5 students Y = 50 dollars X = 3 fail to pay So the ''story'' is that 5 students agree to pay an equal amount for a $50 present (that''s $10 per student). We''re ...”
March 11, 2019
Rich.C@EMPOWERgmat.com posted a reply to A city council will select 2 of 9 available firefighters and in the Problem Solving forum
“Hi All, We''re told that a city council will select 2 of 9 available firefighters and 1 of 6 available police officers to serve on an advisory panel. We''re asked for the number of different groups of 3 people that could serve on the panel. This question is essentially a Combination Formula ...”
March 11, 2019
Rich.C@EMPOWERgmat.com posted a reply to Ramon wants to cut a rectangular board into identical square in the Problem Solving forum
“Hi All, We''re asked to find the minimum number of identical SQUARES that be cut from an 18 in. x 30 in. board without ''wasting'' any of the space. To accomplish this, we need to find a square whose dimensions will evenly divide into both 18 and 30; to find the LEAST number of squares, we''ll ...”
March 11, 2019
Brent@GMATPrepNow posted a reply to Carmen currently works 30 hours per week at her part-time jo in the Data Sufficiency forum
“ Given: Carmen currently works 30 hours per week Target question: If Carmen''s gross hourly wage were to increase by $1.50, how many fewer hours could she work per week and still earn the same gross weekly pay as before the increase? This is a good candidate for rephrasing the target ...”
March 11, 2019
Brent@GMATPrepNow posted a reply to W, X, Y and Z are four different positive integers. When X in the Problem Solving forum
“ Given: When X is divided by Y, the quotient is Z and the remainder is W. ------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 ...”
March 11, 2019
Max@Math Revolution posted a reply to What is the units digit of the product of any five consecuti in the Problem Solving forum
“=> Since one of the five consecutive integers must be a multiple of 5 and one must an even number, their product is a multiple of 10. Thus, the units digits of the product is 0. Therefore, the answer is A. Answer: A”
March 11, 2019
Max@Math Revolution posted a reply to What is the remainder when -12 is divided by -5? in the Problem Solving forum
“=> If we can write A = BQ + R with 0 ≤ R < |B|, then R is the remainder when A is divided by B. -12 = (-5)*3 + 3 Thus, the remainder when -12 is divided by -5 is 3. Therefore, the answer is E. Answer: E”
March 11, 2019
Max@Math Revolution posted a reply to If n is a positive integer, is n a prime number? in the Data Sufficiency forum
“=> Forget conventional ways of solving math questions. For DS problems, the VA (Variable Approach) method is the quickest and easiest way to find the answer without actually solving the problem. Remember that equal numbers of variables and independent equations ensure a solution. Since we ...”
March 11, 2019
Max@Math Revolution posted a reply to Is the average (arithmetic mean) of x, y, and z equal to the in the Data Sufficiency forum
“=> Forget conventional ways of solving math questions. For DS problems, the VA (Variable Approach) method is the quickest and easiest way to find the answer without actually solving the problem. Remember that equal numbers of variables and independent equations ensure a solution. The first ...”
March 11, 2019
Brent@GMATPrepNow posted a reply to What is the hundredths digit of the decimal z? in the Data Sufficiency forum
“Target question: What is the hundredths digit of the decimal z? Statement 1: The tenths digit of 100z is 2 Notice what happens when we take a decimal like 0.123456 and multiply it by 100. We get 12.345 (the tenths digit is 3) In the original decimal, the 3 was in the thousandths place. ...”
March 10, 2019
Brent@GMATPrepNow posted a new topic called W, X, Y and Z are four different positive integers. When X in the Problem Solving forum
“W, X, Y and Z are four different positive integers. When X is divided by Y, the quotient is Z and the remainder is W. If W = X – 7, what is the sum of all possible values of W? A) 19 B) 20 C) 21 D) 22 E) 23 Source: www.gmatprepnow.com Difficulty level: 650 - 700”
March 10, 2019
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 = 23/23 = 1 Answer: C Cheers, Brent”
March 10, 2019
Brent@GMATPrepNow posted a reply to W, X, Y and Z are four different positive integers. in the Data Sufficiency forum
“Target question: What is the value of Z? Given: When X is divided by Y, the quotient is Z and the remainder is W. ------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 ...”
March 8, 2019
Max@Math Revolution posted a new topic called What is the units digit of the product of any five consecuti in the Problem Solving forum
“[GMAT math practice question] What is the units digit of the product of any five consecutive positive integers? A. 0 B. 2 C. 4 D. 6 E. 8”
March 8, 2019
Max@Math Revolution posted a reply to If 0.02 < x < 0.04 and 100 < y < 250, which of t in the Problem Solving forum
“=> Note that (y-x)/(xy) = 1/x – 1/y. 0.02 < x < 0.04 => 1/0.02 > 1/x > 1/0.04 => 50 > 1/x > 25 => 25 < 1/x < 50 100 < y < 250 => 1/100 > 1/y > 1/250 => 0.01 > 1/y > 0.004 => 0.004 < 1/y < 0.01 So, 25 – 0.01 ...”
March 8, 2019
Max@Math Revolution posted a new topic called If n is a positive integer, is n a prime number? in the Data Sufficiency forum
“[GMAT math practice question] If n is a positive integer, is n a prime number? 1) n is the least factor of 77 greater than 1 2) n has exactly two factors”
March 8, 2019
Max@Math Revolution posted a reply to Is a triangle, with one side of length 12, inscribed in a ci in the Data Sufficiency forum
“=> Forget conventional ways of solving math questions. For DS problems, the VA (Variable Approach) method is the quickest and easiest way to find the answer without actually solving the problem. Remember that equal numbers of variables and independent equations ensure a solution. The first ...”
March 8, 2019
Brent@GMATPrepNow posted a reply to OG 2017 Ratio Question in the Data Sufficiency forum
“Target question: What is the total number of articles of clothing in the closet? Given: The ratio of the number of shirts to the number of dresses to the number of jackets in the closet is 9:4:5, respectively. If shirts : dresses : jackets = 9 : 4 : 5, then there are infinitely many ...”
March 7, 2019
Brent@GMATPrepNow posted a new topic called W, X, Y and Z are four different positive integers. in the Data Sufficiency forum
“W, X, Y and Z are four different positive integers. When X is divided by Y, the quotient is Z and the remainder is W. What is the value of Z? 1) W = X – 4 2) W + Z = 4 Difficulty level: 650 – 700 Source: www.gmatprepnow.com”
March 7, 2019
Brent@GMATPrepNow posted a reply to 60 DAY STUDY GUIDE ENQUIRY in the Ask a GMAT Prep Now representative forum
“Sorry, but there are no plans to update the 60-day guide in the near future. Cheers, Brent”
March 7, 2019
Max@Math Revolution posted a new topic called What is the remainder when -12 is divided by -5? in the Problem Solving forum
“[GMAT math practice question] What is the remainder when -12 is divided by -5? A. -3 B. -2 C. 0 D. 2 E. 3”
March 7, 2019
Max@Math Revolution posted a reply to If x and y are positive integers and (x-y)^2+y^2=25, which o in the Problem Solving forum
“=> The possible values of the pair (x-y,y), with x and y positive, are (0,5), (3,4), (-3,4), (4,3) and (-4,3). So, (x,y) = (5,5), (7,4), (1,4), (7,3) or (-1,3). Thus, x could be 5, 7 or 1. Therefore, B is the answer. Answer: B”
March 7, 2019
Max@Math Revolution posted a new topic called Is the average (arithmetic mean) of x, y, and z equal to the in the Data Sufficiency forum
“[GMAT math practice question] Is the average (arithmetic mean) of x, y, and z equal to their median? 1) y is the average (arithmetic mean) of x, y, and z 2) z = 2y - x”
March 7, 2019
Max@Math Revolution posted a reply to When 32 is divided by k, the remainder is k-3. What is the in the Data Sufficiency forum
“=> Forget conventional ways of solving math questions. For DS problems, the VA (Variable Approach) method is the quickest and easiest way to find the answer without actually solving the problem. Remember that equal numbers of variables and independent equations ensure a solution. The first ...”
March 7, 2019
Brent@GMATPrepNow posted a reply to What is the sum of all of the integers in the chart above? in the Problem Solving forum
“Always check the answer choices BEFORE solving the question!! Since the answer choices are nicely spread apart, we can be quite aggressive in our estimation Let''s add the 5 numbers in each COLUMN COLUMN 1: Sum ≈500 COLUMN 2: Sum ≈-1000 COLUMN 3: Sum ≈1500 COLUMN 4: Sum ≈-2000 ...”
March 6, 2019
Brent@GMATPrepNow posted a reply to If 0.02 < x < 0.04 and 100 < y < 250, which of t in the Problem Solving forum
“We can use a nice (and often tested) fraction property that says: (a - b)/c = a/c - bc So, (y-x)/(xy) = y/xy - x/xy = 1/x - 1/y That''s better! So, we''re now looking for a possible value of 1/x - 1/y Let''s look at some EXTREME values. We can MAXIMIZE the value of 1/x - 1/y by MAXIMIZING ...”
March 6, 2019
Brent@GMATPrepNow posted a reply to For every even positive integer m, f(m) represents the in the Problem Solving forum
“f(24) = 2 x 4 x 6 x 8 x 10 x 12 x 14 x 16 x 18 x 20 x 22 x 24 Rewrite as prime factorization: f(24) = 2 x (2)(2) x (2)(3) x (2)(2)(2) x (2)(5) x (2)(2)(3) x (2)(7) x (2)(2)(2)(2) x (2)(3)(3) x (2)(2)(5) x (2)(11) x (2)(2)(2)(3) Answer: E ASIDE: As you can see from the answer choice, I ...”
March 6, 2019
Max@Math Revolution posted a new topic called If 0.02 < x < 0.04 and 100 < y < 250, which of the following in the Problem Solving forum
“[GMAT math practice question] If 0.02 < x < 0.04 and 100 < y < 250, which of the following could be the value of (y-x)/(xy)? A. 10 B. 20 C. 30 D. 50 E. 100”
March 6, 2019
Max@Math Revolution posted a reply to How many committees can be formed comprising 2 male members in the Problem Solving forum
“=> There are 4C2 ways to select 2 men from 4 men, 5C3 ways to select 3 women from 5 women and 6C3 ways to select 3 juniors from 6 juniors. Therefore, the total number of possible committees is 4C2*5C3*6C3 = {(4*3)/(2*1)}{(5*4*3)/(3*2*1)}{(6*5*4)/(3*2*1)} = 6*10*20 = 1200. Therefore, B is ...”
March 6, 2019
Max@Math Revolution posted a new topic called Is a triangle, with one side of length 12, inscribed in a ci in the Data Sufficiency forum
“[GMAT math practice question] Is a triangle, with one side of length 12, inscribed in a circle a right triangle? 1) The area of the circle is 36π. 2) The circumference of the circle is 12π.”
March 6, 2019
Max@Math Revolution posted a reply to k is a positive integer. When 2^{-k/2} ≤ 1/1,024, k=? in the Data Sufficiency forum
“=> Forget conventional ways of solving math questions. For DS problems, the VA (Variable Approach) method is the quickest and easiest way to find the answer without actually solving the problem. Remember that equal numbers of variables and independent equations ensure a solution. The first ...”
March 6, 2019
Max@Math Revolution posted a new topic called [Math Revolution] Practice “Math Questions of the Day” in the GMAT Math forum
“To help you sharpen your math skills and hit your target score of Q49-51, we are sending you 4 math questions (2 DS, 2 PS) and solutions regularly. These questions are the types of questions appearing in GMAT exam frequently. Please Click the link for solutions. ...”
March 6, 2019
Brent@GMATPrepNow posted a reply to Is xy>3? in the Data Sufficiency forum
“Target question: Is xy > 3 ? Statement 1: (7^x) > 729 Since there''s no information about y, we cannot answer the target question with certainty. Statement 1 is NOT SUFFICIENT Statement 2: (9^y) = 7 Since there''s no information about x, we cannot answer the target question with ...”
March 5, 2019
ceilidh.erickson posted a reply to For similar homes and comparable residents, home insurance f in the Critical Reasoning forum
“When we''re asked to EVALUATE an argument, we need to establish the conclusion of the argument and its supporting premises. We then need to determine what information is MISSING. Premises: - For similar homes and comparable residents, home insurance for theft has always cost more in ...”
March 5, 2019
ceilidh.erickson posted a reply to Quasars are so distant that their light has taken billions o in the Sentence Correction forum
“For more on when to use PAST PERFECT v. SIMPLE PAST tenses, see: https://www.beatthegmat.com/og-10-native-american-burial-sites-t45325.html#577377 https://www.beatthegmat.com/by-1945-the-us-had-been-t274960.html#714092”
March 5, 2019
ceilidh.erickson posted a reply to Quasars are so distant that their light has taken billions o in the Sentence Correction forum
“This question is testing VERB TENSES. When you see differences in verb tense in answer choices, ask yourself: "when are these events happening in time?" The intended meaning of the sentence should be: - light left these quasars long in the past - we''re just seeing that light now ...”
March 5, 2019
ceilidh.erickson posted a reply to For the 5 days shown in the graph, how many kilowatt-hours in the Problem Solving forum
“To find the median, first list the daily kilowatt-hours in order: 19, 24, 27, 29, 31 The median = 27 To find the average, we could add up all the terms and divide by 5. Instead, though, just see how much each term differs from the median: 19 --> 27 - 8 24 --> 27 - 3 27 29 --> 27 ...”
March 5, 2019
ceilidh.erickson posted a reply to Among the members of the Malmo family, there are three times in the Problem Solving forum
“Overlapping Sets are a common question type on the GMAT, and the double-set matrix is often the easiest way to solve. For more on how to use the matrix, see: https://www.beatthegmat.com/for-what-percent-of-those-tested-for-a-certain-infection-was-t303715.html#818652 ...”
March 5, 2019
ceilidh.erickson posted a reply to Among the members of the Malmo family, there are three times in the Problem Solving forum
“This is an OVERLAPPING SETS question. The best way to approach it is with a DOUBLE-SET MATRIX: https://i.postimg.cc/GBrL4B72/Screenshot-2019-03-05-13-38-45.png If there are three times as many members who do not wear glasses as members who do, we can express the total who wear glasses as x and ...”
March 5, 2019
ceilidh.erickson posted a reply to Set X consists of the positive multiples of 5, and set Y in the Problem Solving forum
“There is no real shortcut to this problem; we simply have to count the results. Set X: 15 3 * 10 = 30 3 * 15 = 45 3 * 20 = 60 3 * 25 = 75 3 * 30 = 90 Anything greater than 30 would yield a product greater than 100, so those are the only results for 3. Now try 5: 5 * 5 = 25 5 * 10 = 50 ...”
March 5, 2019
Brent@GMATPrepNow posted a reply to x is the product of all even numbers from 2 to 50, inclusive in the Problem Solving forum
“Here''s a very similar (official) question to practice with: https://www.beatthegmat.com/arthemetic-question-on-factors-and-prime-numbers-t275643.html Cheers, Brent”
March 5, 2019
Brent@GMATPrepNow posted a reply to Joey works at a clothing store and receives an employee in the Problem Solving forum
“Let R = REGULAR price of the item Joey and receives an employee discount of 10 percent off the regular price of any item. So, Joey pays 90% of the REGULAR price. In other words, 0.9R = the DISCOUNT price that Joey actually pays What is the regular price of an item that Joey purchases for ...”
March 5, 2019
Max@Math Revolution posted a new topic called If x and y are positive integers and (x-y)^2+y^2=25, which o in the Problem Solving forum
“[GMAT math practice question] If x and y are positive integers and (x-y)^2+y^2=25, which of the following could be the value of x? A. 6 B. 7 C. 8 D. 9 E. 10”
March 5, 2019
Max@Math Revolution posted a new topic called When 32 is divided by k, the remainder is k-3. What is the in the Data Sufficiency forum
“[GMAT math practice question] When 32 is divided by k, the remainder is k-3. What is the value of k? 1) k > 20 2) k < 40”
March 5, 2019
Brent@GMATPrepNow posted a reply to In how many ways can 16 different gits be divided among four in the Problem Solving forum
“Let''s say the children are named A, B, C, and D Stage 1: Select 4 gifts to give to child A Since the order in which we select the 4 gifts does not matter, we can use combinations. We can select 4 gifts from 16 gifts in 16C4 ways (= 16!/(4!)(12!)) So, we can complete stage 1 in ...”
March 4, 2019
Max@Math Revolution posted a new topic called How many committees can be formed comprising 2 male members in the Problem Solving forum
“[GMAT math practice question] How many committees can be formed comprising 2 male members selected from 4 men, 3 female members selected from 5 women, and 3 junior members selected from 6 juniors? A. 900 B. 1200 C. 1500 D. 1800 E. 2400”
March 4, 2019
Max@Math Revolution posted a new topic called k is a positive integer. When 2^{-k/2} ≤ 1/1,024, k=? in the Data Sufficiency forum
“[GMAT math practice question] k is a positive integer. When 2^{-k/2} ≤ 1/1,024, k=? 1) k is an integer less than 21 2) k is an integer greater than 12”
March 4, 2019
Max@Math Revolution posted a reply to Which of following satisfies the inequality (2x-49)(x^2+6x+1 in the Problem Solving forum
“=> x^2+6x+10 = x^2+6x+9 + 1 = (x+3)^2+1 ≥ 1 > 0. Since x^2+6x+10 > 0, we have (2x-49)(x^2+6x+10) ≤ 0, which implies that 2x – 49 < 0. So, 2x < 49, and x < 24.5. Therefore, the answer is A. Answer: A”
March 4, 2019
Max@Math Revolution posted a reply to (x-a)^2 + (y-b)^2 = r^2 is the equation of a circle with rad in the Problem Solving forum
“=> x^2 + y^2 – 10x + 4y = 20 => x^2 – 10x + y^2 + 4y = 20 => x^2 – 10x + 25 + y^2 + 4y + 4 = 20 + 25 + 4 => (x-5)^2 + (y+2)^2 = 49 => (x-5)^2 + (y+2)^2 = 7^2 Thus the circle has center (5,-2) and radius 7. Therefore, the answer is D. Answer: D”
March 4, 2019
Max@Math Revolution posted a reply to If m and n are prime numbers, is m^2 + n^2 an even number? in the Data Sufficiency forum
“=> Forget conventional ways of solving math questions. For DS problems, the VA (Variable Approach) method is the quickest and easiest way to find the answer without actually solving the problem. Remember that equal numbers of variables and independent equations ensure a solution. In order ...”
March 4, 2019
Max@Math Revolution posted a reply to Is x = y? 1) x ≤ y 2) |x| ≥ |y| in the Data Sufficiency forum
“=> Forget conventional ways of solving math questions. For DS problems, the VA (Variable Approach) method is the quickest and easiest way to find the answer without actually solving the problem. Remember that equal numbers of variables and independent equations ensure a solution. Since we ...”
March 4, 2019
Brent@GMATPrepNow posted a reply to The positive two-digit integers x and y have the same digits in the Problem Solving forum
“Another approach is to test some values for x and y that satisfy the given information. Positive two-digit integers x and y have the same digits, but in reverse order So, it COULD be the case that x = 12 and y = 21 Which of the following must be a factor of x + y? x + y = 12 + 21 = 33 ...”
March 3, 2019
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 ...”
March 2, 2019
Rich.C@EMPOWERgmat.com posted a reply to Two hoses are pouring water into an empty pool. Hose 1 alone in the Problem Solving forum
“Hi All, This question is a variation of a ''Work Formula'' question (it involves 2 ''entities'' working on the same task together), so we can use the Work Formula to solve it. Work = (A)(B)/(A+B) where A and B are the individual times that it takes the 2 entities to complete the task on their ...”
March 2, 2019
Rich.C@EMPOWERgmat.com posted a reply to Range Problem.,... in the Problem Solving forum
“Hi All, We''re told that Set X consists of PRIME numbers {3, 11, 7, K, 17, 19}, the integer Y represents the PRODUCT of all elements in Set X and 11Y is an EVEN number. We''re asked for the RANGE of Set X. This question is based on several Number Property rules - and doesn''t actually require ...”
March 2, 2019
Rich.C@EMPOWERgmat.com posted a reply to In how many ways can the letters D, I, G, I, T be arranged in the Problem Solving forum
“Hi All, We''re asked to find the number of ways that the letters D, I, G, I, T be arranged so that the two I''s are NOT next to each other. Since the two "I"s cannot be side-by-side, there are a limited number of ways to arrange the 5 letters. As such, with a little permutation math ...”
March 2, 2019
Brent@GMATPrepNow posted a reply to Median of set T in the Problem Solving forum
“If we have a set of y INTEGERS, there are two possible cases when it comes to the MEDIAN. Case a: y is an ODD number, in which case the MEDIAN equals the one middle integer (when all of the integers are arranged in ascending order). In this case, the median must be an integer. Case b: y is an ...”
March 2, 2019
Max@Math Revolution posted a new topic called Which of following satisfies the inequality (2x-49)(x^2+6x+1 in the Problem Solving forum
“[GMAT math practice question] Which of following satisfies the inequality (2x-49)(x^2+6x+10) < 0? A. 24 B. 25 C. 50 D. 51 E. 99”
March 1, 2019
Max@Math Revolution posted a reply to How many whole numbers between 100 and 400, inclusive, conta in the Problem Solving forum
“=> There are 19 such numbers with hundreds digit 1: 102, 112, 120, 121, …, 129, 132, 142, …, 192. There are 100 such numbers with hundreds digit 2: 200, 201, 202, 203, …, 299. There are 19 such numbers with hundreds digit 3: 302, 312, 320, 321, …, 329, 332, 342, …, 392. Thus, ...”
March 1, 2019
Max@Math Revolution posted a new topic called If m and n are prime numbers, is m^2 + n^2 an even number? in the Data Sufficiency forum
“[GMAT math practice question] If m and n are prime numbers, is m^2 + n^2 an even number? 1) m > 10 2) n > 20”
March 1, 2019
Max@Math Revolution posted a reply to n is a positive integer. What is the remainder when n is div in the Data Sufficiency forum
“=> Forget conventional ways of solving math questions. For DS problems, the VA (Variable Approach) method is the quickest and easiest way to find the answer without actually solving the problem. Remember that equal numbers of variables and independent equations ensure a solution. Since we ...”
March 1, 2019
Rich.C@EMPOWERgmat.com posted a reply to The product of the digits of the four-digit number h is 36. in the Problem Solving forum
“Hi All, We''re told that the product of the digits of the four-digit number H is 36 and no two digits of H are identical. We''re asked for the number of different possible values of H. While this question might seem complex, most of the work is based on basic Arithmetic (and some Permutation ...”
March 1, 2019
Rich.C@EMPOWERgmat.com posted a reply to A motorcycle travels at a speed of x kilometers per p hours. in the Problem Solving forum
“Hi All, We''re told that a motorcycle travels at a speed of X KILOMETERS per P HOURS. We''re asked for the number of METERS it will travel in S SECONDS, in terms of S, P and X. (xps ≠ 0; 1 kilometer = 1000 meters). This question can be solved in a number of different ways, including by TESTing ...”
March 1, 2019
Rich.C@EMPOWERgmat.com posted a reply to All assets in Karina's investment portfolio are divided in the Problem Solving forum
“Hi All, We''re told that all assets in Karina''s investment portfolio are divided between an IRA, 401k, and two separate taxable accounts and that NO two accounts have the SAME amount of money and all four have at least SOME money in them. If each account has a whole-number percent of Karina''s ...”
March 1, 2019
Rich.C@EMPOWERgmat.com posted a reply to Vivian drives to her sister’s house and back. She takes th 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 ...”
March 1, 2019
Rich.C@EMPOWERgmat.com posted a reply to Tips for improving GMAT from 500-700 in the GMAT Strategy forum
“Hi Rahufalb, To start, the only practical way to properly measure your overall Test-taking skills during the course of your studies is to take a FULL-LENGTH CAT under realistic conditions (meaning that you should take a FULL CAT - with the Essay and IR sections, in a location that is NOT your ...”
March 1, 2019
Brent@GMATPrepNow posted a reply to Two positive numbers differ by 12 and their reciprocals in the Problem Solving forum
“Two positive numbers differ by 12 Let x = the smaller number So x + 12 = the larger number NOTE: our goal is to find the value of x(x + 12) Their reciprocals differ by 4/5 We get: 1/x - 1/(x+12) = 4/5 Multiply both sides by x to get: 1 - x/(x + 12) = 4x/5 Multiply both sides by 5 to get: 5 ...”
February 28, 2019
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: ...”
February 28, 2019
Max@Math Revolution posted a new topic called (x-a)^2 + (y-b)^2 = r^2 is the equation of a circle with rad in the Problem Solving forum
“(x-a)^2 + (y-b)^2 = r^2 is the equation of a circle with radius r and center (a,b). What is the radius of the circle with equation x^2 + y^2 – 10x + 4y = 20? A. 4 B. 5 C. 6 D. 7 E. 8”
February 28, 2019
Max@Math Revolution posted a new topic called Is x = y? 1) x ≤ y 2) |x| ≥ |y| in the Data Sufficiency forum
“Is x = y? 1) x ≤ y 2) |x| ≥ |y|”
February 28, 2019
Max@Math Revolution posted a reply to A is the set of 6-digit positive integers whose first three in the Problem Solving forum
“Each number n in the set A is an integer of the form “xyz,xyz”. So, n = 10^5x + 10^4y + 10^3z + 10^2x + 10y + z = 10^3(10^2x + 10y + z) + (10^2x + 10y + z ) = 1000(10^2x + 10y + z) + (102x + 10y + z ) = 1001(10^2x + 10y + z ) = 11*91(10^2x + 10y + z ) Thus, n is a multiple of 11. ...”
February 28, 2019
Max@Math Revolution posted a reply to If n is an integer, is (n+1)(n+2)(n+3) divisible by 12? 1) n in the Data Sufficiency forum
“Forget conventional ways of solving math questions. For DS problems, the VA (Variable Approach) method is the quickest and easiest way to find the answer without actually solving the problem. Remember that equal numbers of variables and independent equations ensure a solution. The first step of ...”
February 28, 2019
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, ...”
February 28, 2019
Brent@GMATPrepNow posted a reply to A certain club has 20 members. What is the ratio of the in the Problem Solving forum
“5-member committees Since the order in which we select the committee members does not matter, we can use COMBINATIONS We can select 5 people from 20 people in 20C5 ways 20C5 = (20)(19)(18)(17)(16)/(5)(4)(3)(2)(1) 4-member committees Since the order in which we select the committee members ...”
February 28, 2019
Brent@GMATPrepNow posted a reply to Train A and Train B began traveling towards each other from in the Problem Solving forum
“This is a SHRINKING GAP question. Train A traveled at 35 miles per hour and Train B traveled at 25 miles per hour, 35 mph + 25 mph = 60 mph So, the gap CLOSES at a rate of 60 mph Train A and Train B began traveling towards each other from opposite ends of a 500-mile long track at 1:00 PM ...”
February 28, 2019
Brent@GMATPrepNow posted a reply to In 1990 the budgets for projects Q and V were $660,000 and in the Problem Solving forum
“One approach is to treat this is a rate question. In 1990 the GAP BETWEEN V''s budget and Q''s budget was $120,000 ($780,000 - $660,000 = $120,000) Each year, the budget for Q increased by $30,000 and the budget for V decreased by $10,000. In other words, the GAP BETWEEN the budgets ...”
February 28, 2019
Max@Math Revolution posted a new topic called How many whole numbers between 100 and 400, inclusive, conta in the Problem Solving forum
“How many whole numbers between 100 and 400, inclusive, contain the digit 2? A. 100 B. 125 C. 138 D. 145 E. 150”
February 27, 2019
Max@Math Revolution posted a new topic called n is a positive integer. What is the remainder when n is div in the Data Sufficiency forum
“n is a positive integer. What is the remainder when n is divided by 3? 1) n^2 has remainder 1 when it is divided by 3 2) n has remainder 7 when it is divided by 9”
February 27, 2019
Max@Math Revolution posted a reply to For positive integers m and n, is m^n a perfect square? in the Data Sufficiency forum
“Forget conventional ways of solving math questions. For DS problems, the VA (Variable Approach) method is the quickest and easiest way to find the answer without actually solving the problem. Remember that equal numbers of variables and independent equations ensure a solution. The first step of ...”
February 27, 2019
Max@Math Revolution posted a reply to (b-a)/ab = 1/a – 1/b. What is the value of 1/2 + 1/6 + 1/1 in the Problem Solving forum
“1/2 + 1/6 + 1/12 + … + 1/90 = 1/(1*2) + 1/(2*3) + 1/(3*4) + … + 1(9*10) = (2-1)/(1*2) + (3-2)/(2*3) + (4-3)/(3*4) + … + (10-9)/(9*10) = (1/1 – 1/2) + (1/2 – 1/3) + (1/3-1/4) + … + (1/9 – 1/10) = 1/1 – 1/10 = 9/10 Therefore, D is the answer.”
February 27, 2019
Rich.C@EMPOWERgmat.com posted a reply to Materials for solving. in the GMAT Strategy forum
“Hi Zaidf1997, It sounds like you''re just beginning your studies. Have you done any studying so far or are you just beginning? If you are just starting out, 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 ...”
February 26, 2019
ceilidh.erickson posted a reply to John has to hammer 100 railroad spikes for a new line his in the Problem Solving forum
“If John completed the entire task by himself, the time would be 100/8 --> 25/2, or 12 and 1/2 hrs. He would be halfway done after 6 and 1/4 hrs, and there would be 50 spikes remaining. If he and Paul work together at the same rate for the remaining 50 spikes, their combined rate would be ...”
February 26, 2019
ceilidh.erickson posted a reply to Passengers must exit airplanes swiftly after accidents, sinc in the Critical Reasoning forum
“We need to select an answer that is consistent with the given information: - Passengers must exit airplanes swiftly after accidents, since gases released following accidents are toxic to humans and often explode soon after being released. - In order to prevent passenger deaths from gas ...”
February 26, 2019
ceilidh.erickson posted a reply to Not Only But Also vs Not Only, But Also in the Sentence Correction forum
“Generally we don''t need commas to separate a simple list of 2 things with conjunctions. It doesn''t matter whether it''s a simple conjunction (e.g. "and") or a complex conjunction structure (e.g. "not only__ but also__") I like pomegranates and figs. I like not only ...”
February 26, 2019
ceilidh.erickson posted a reply to The possible long-term health risks to airline personnel who in the Sentence Correction forum
“This question is testing SUBJECT-VERB agreement. The subject of this sentence is RISKS: The ... risks (to airline personnel (who ...)) has been a concern ... The GMAT often puts long, distracting modifiers between the subject & the verb to confuse your ear. If you notice a split between ...”
February 26, 2019
ceilidh.erickson posted a reply to According to a recent study, hand sanitizers require a 60 pe in the Sentence Correction forum
“This question is testing IDIOMS. The correct idiom in this case is "require ___ to do ____." (A) require a 60 percent minimum alcohol concentration for the killing of - "for the killing of" is unnecessarily wordy. "To kill" is preferred. (B) require that ...”
February 26, 2019
ceilidh.erickson posted a reply to A middleweight black hole weighs in at roughly 500 solar mas in the Sentence Correction forum
“This question is testing simple parallelism. The correct parallel structure (logically and grammatically) is: 1. hundreds of times more massive than ___ 2. but thousands or even millions of times less massive than ____ (A) thousands or even millions of times less in its mass as - ...”
February 26, 2019
ceilidh.erickson posted a reply to Thomas Mann's novel Doctor Faustus offers an examination not in the Sentence Correction forum
“This two-part parallelism - also known as CLOSED PARALLELISM - is very common on the GMAT. Any time you see the following: BOTH ____ AND ____ EITHER ____ OR ______ NOT ONLY _____BUT ALSO _______ NOT ________ BUT _________ etc, ... you need to make sure that what comes right after the ...”
February 26, 2019
ceilidh.erickson posted a reply to Thomas Mann's novel Doctor Faustus offers an examination not in the Sentence Correction forum
“Be careful - prepositions do not have to be the same in order to be parallel! You''re over-applying parallelism where you don''t need it. For example, I could say: I jumped both OVER the rocks and INTO the lake. As long as both prepositional phrases fit (grammatically, idiomatically, and ...”
February 26, 2019
Brent@GMATPrepNow posted a reply to Is xy+zt+yz+tx positive? in the Data Sufficiency forum
“Target question: Is xy + zt + yz + tx positive? Statement 1: |x| = |y| = |z| = t Let''s TEST some values. There are several values of x, y, z and t that satisfy statement 1. Here are two: Case a: x = y = z = t = 1. In this case, xy + zt + yz + tx = (1)(1) + (1)(1) + (1)(1) + (1)(1) = 4. ...”
February 26, 2019
Brent@GMATPrepNow posted a reply to A manufacturer makes umbrellas at the cost of c dollars per in the Problem Solving forum
“This is a tough one to use the INPUT-OUTPUT approach, but here is goes: Let c = $2 (it cost $2 to make each umbrella) Let x = 10 (we make 10 umbrellas) Let r = $5 (the retail price is $5 per umbrella) Let b = $0 (the below-cost sale price is $0 per umbrella) So, the manufacturer made 10 ...”
February 26, 2019
Max@Math Revolution posted a new topic called A is the set of 6-digit positive integers whose first three in the Problem Solving forum
“A is the set of 6-digit positive integers whose first three digits are same as their last three digits, written in the same order. Which of the following numbers must be a factor of every number in the set A? A. 7 B. 11 C. 17 D. 19 E. 23”
February 26, 2019
Max@Math Revolution posted a new topic called If n is an integer, is (n+1)(n+2)(n+3) divisible by 12? 1) n in the Data Sufficiency forum
“If n is an integer, is (n+1)(n+2)(n+3) divisible by 12? 1) n is an even number. 2) n is a multiple of 4.”
February 26, 2019
Max@Math Revolution posted a new topic called (b-a)/ab = 1/a – 1/b. What is the value of 1/2 + 1/6 + 1/12 in the Problem Solving forum
“(b-a)/ab = 1/a – 1/b. What is the value of 1/2 + 1/6 + 1/12 + … + 1/90? A. 4/5 B. 5/6 C. 8/9 D. 9/10 E. 11/12”
February 25, 2019
Max@Math Revolution posted a new topic called For positive integers m and n, is m^n a perfect square? in the Data Sufficiency forum
“For positive integers m and n, is m^n a perfect square? 1) The five-digit integer, 12,3m0 is a multiple of 4 2) The five-digit integer, 23,4n5 is a multiple of 9”
February 25, 2019
Brent@GMATPrepNow posted a reply to How many positive two-digit numbers are odd, not divisible b in the Problem Solving forum
“After about 30 seconds, I recognized that I couldn''t see a nice straightforward solution (one that doesn''t involve considering multiple cases), so I had 3 options: 1) Keep searching for a nice straightforward solution 2) Guess and move on 3) List the possible outcomes Since the answer ...”
February 25, 2019
Brent@GMATPrepNow posted a reply to Nine identical chips are numbered from 1 to 9 (one different in the Problem Solving forum
“ODDS: 1, 3, 5, 7, 9 EVENS: 2, 4, 6, 8 Take the task of removing the 9 chips and break it into stages. Stage 1: Select an ODD number to be the 1st selection There are 5 ODDs to choose from. So, we can complete stage 1 in 5 ways Stage 2: Select an EVEN number to be the 2nd selection ...”
February 25, 2019
Brent@GMATPrepNow posted a reply to All assets in Karina's investment portfolio are divided betw 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 ...”
February 25, 2019
Brent@GMATPrepNow posted a reply to Vivian drives to her sister’s house and back. She takes th 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 ...”
February 25, 2019
Rich.C@EMPOWERgmat.com posted a reply to Ten theater students are to begin work on a set for a in the Problem Solving forum
“Hi All, We''re told that 10 theater students are to begin work on a set for a musical. Working at a constant rate, they will finish the set in 60 days, but the director of the musical decides they need to finish in 50 days. We''re asked for the number of ADDITIONAL theater students we would ...”
February 24, 2019
Rich.C@EMPOWERgmat.com posted a reply to A circular lawn with a radius of 5 meters is surrounded by a in the Problem Solving forum
“Hi All, We''re told that a circular lawn with a radius of 5 meters is surrounded by a circular walkway that is 4 meters wide. We''re asked for the area of the walkway. This is an example of a ''punch out'' question - we need to find the area of the ENTIRE shape and then ''punch out'' the part ...”
February 24, 2019
Rich.C@EMPOWERgmat.com posted a reply to Kim has 40 percent more money than Sal and Sal has 20 in the Problem Solving forum
“Hi All, We''re told that Kim has 40 percent MORE money than Sal, Sal has 20 percent LESS money than Phil and Sal and Phil have a combined total of $1.80. We''re asked for the amount of money that Kim has. This question can be approached in a couple of different ways, including some brute-force ...”
February 24, 2019
Brent@GMATPrepNow posted a reply to In a certain class, the ratio of girls to boys is 5:4. How m in the Data Sufficiency forum
“ Given: In a certain class, the ratio of girls to boys is 5:4. Let G = number of girls in the class Let B = number of boys in the class We can write: G/B = 5/4 Cross multiply to get: 4G = 5B Rearrange to get: 4G - 5B = 0 Target question: What is the value of G Statement 1: If four ...”
February 24, 2019
Brent@GMATPrepNow posted a reply to Kim has 40 percent more money than Sal and Sal has 20 in the Problem Solving forum
“Let x = Phil''s money Sal has 20 percent LESS money than Phil So, Sal''s money = (Phil''s money) - (20% Phil''s money) = x - (20% of x) = x - 0.2x = 0.8x Kim has 40 percent more money than Sal So, Kim''s money = (Sal''s money) + (40% Sal''s money) = (0.8x) + (40% of 0.8x) = ...”
February 24, 2019
Brent@GMATPrepNow posted a reply to A straight line in the xy-plane has a slope of 2 and a in the Problem Solving forum
“The question conveniently gives us the information to write the equation of the line in slope y-intercept form, y = mx + b, where m = slope and b = the y-intercept. Line in the xy-plane has a slope of 2 and a y-intercept of 2 So, the equation of the line is: y = 2x + 2 On this line, what is ...”
February 24, 2019
Max@Math Revolution posted a reply to If 1/x-1/y=1/z, what is the value of y, in terms of x and z? in the Problem Solving forum
“=> Making y the subject of the equation 1/x – 1/y = 1/z yields 1/y = 1/x – 1/z = (z-x)/xz, and y = xz/(z-x). Therefore, the answer is A. Answer: A”
February 24, 2019
Max@Math Revolution posted a reply to What is the greatest positive three-digit number that is div in the Problem Solving forum
“=> The question asks for the value of the greatest positive three-digit multiple of lcm(2,3,4,5,6,7), where lcm(2,3,4,5,6,7) is the least common multiple of 2, 3, 4, 5, 6 and 7. lcm(2,3,4,5,6,7) = 2^2*3*5*7 = 420. There are two positive three-digit integers that are multiples of 420: 420 ...”
February 24, 2019
Max@Math Revolution posted a reply to a, b, and c are positive integers. Is a+b+c an odd number? in the Data Sufficiency forum
“=> Forget conventional ways of solving math questions. For DS problems, the VA (Variable Approach) method is the quickest and easiest way to find the answer without actually solving the problem. Remember that equal numbers of variables and independent equations ensure a solution. Since we ...”
February 24, 2019
Max@Math Revolution posted a reply to f(x)=x^{2n}+x^n+1, where n is an integer. Is f(x)=1? in the Data Sufficiency forum
“=> Forget conventional ways of solving math questions. For DS problems, the VA (Variable Approach) method is the quickest and easiest way to find the answer without actually solving the problem. Remember that equal numbers of variables and independent equations ensure a solution. The first ...”
February 24, 2019
Brent@GMATPrepNow posted a reply to If y >= 0, What is the value of x? in the Data Sufficiency forum
“Target question: What is the value of x? Given: y ≥ 0 Statement 1: |x - 3| ≥ y Let''s TEST some values. There are several values of x and y that satisfy statement 1. Here are two: Case a: x = 10 and y = 2. We get |10 - 3| ≥ 2, which evaluates to be 7 ≥ 2, which satisfies ...”
February 23, 2019
Brent@GMATPrepNow posted a reply to The total of company C's assets in 1994 was 300% greater in the Problem Solving forum
“The total of company C''s assets in 1992 was N dollars Company C''s assets in 1993 was 400% greater than the total in 1992 So, 1993 assets = (1992 assets) + (400% of 1992 assets) = (N) + (400% of N) = (N) + (400/100 x N) = N + 4N = 5N Company C''s assets in 1994 was 300% greater than the ...”
February 23, 2019
Brent@GMATPrepNow posted a reply to At a bakery, the price of a bagel ranges between $0.65 and $ in the Problem Solving forum
“The least expensive price for a bagel is $0.65 If a customer purchases 12 bagels (at $0.65 each), then he/she receives 13 bagels. So, the minimum amount that a customer could pay to receive 13 bagels = 12 x $0.65 = $7.80 Answer: B Cheers, Brent”
February 23, 2019
Brent@GMATPrepNow posted a reply to a, b, and c are positive integers. Is a+b+c an odd number? in the Data Sufficiency forum
“ Given: a, b, and c are positive integers. Target question: Is a + b + c an odd number? Statement 1: ab is an odd number No information about c. NOT SUFFICIENT Statement 2: c is an odd number No information about a or b. NOT SUFFICIENT Statements 1 and 2 combined If ab ...”
February 22, 2019
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 ...”
February 22, 2019
Brent@GMATPrepNow posted a reply to If 1/x-1/y=1/z, what is the value of y, in terms of x and z? in the Problem Solving forum
“We can also solve the question algebraically. GIVEN: 1/x - 1/y = 1/z Multiply both sides by x to get: 1 - x/y = x/z Multiply both sides by y to get: y - x = xy/z Multiply both sides by z to get: yz - xz = yx Rearrange to get y terms on one side: yz - yx = xz Factor left side: y(z - x) = ...”
February 22, 2019
Max@Math Revolution posted a new topic called If 1/x-1/y=1/z, what is the value of y, in terms of x and z? in the Problem Solving forum
“[GMAT math practice question] If 1/x-1/y=1/z, what is the value of y, in terms of x and z? A. xz/(z-x) B. xz/(x-z) C. x/z(z-x) D. z/x(x-z) E. xz(z-x)”
February 22, 2019
Max@Math Revolution posted a reply to What is the largest digit n for which the number 123,45n is in the Problem Solving forum
“=> Recall that a number is divisible by 3 if and only if the sum of its digits is divisible by 3. The sum of the digits of 123,45n is 1 + 2 + 3 + 4 + 5 + n = n + 15. This is divisible by 3 exactly when n is divisible by 3. So, n must be a multiple of 3. Thus, the largest digit, n is 9. ...”
February 22, 2019
Max@Math Revolution posted a new topic called a, b, and c are positive integers. Is a+b+c an odd number? in the Data Sufficiency forum
“[GMAT math practice question] a, b, and c are positive integers. Is a + b + c an odd number? 1) ab is an odd number 2) c is an odd number”
February 22, 2019
Max@Math Revolution posted a reply to If a and b are positive integers, is a+b divisible by 7? in the Data Sufficiency forum
“=> Forget conventional ways of solving math questions. For DS problems, the VA (Variable Approach) method is the quickest and easiest way to find the answer without actually solving the problem. Remember that equal numbers of variables and independent equations ensure a solution. The first ...”
February 22, 2019
Brent@GMATPrepNow posted a reply to Last year the range of the annual salaries of the 100 in the Problem Solving forum
“A quick solution is to assign some values to the highest paid and lowest paid workers Let $10,000 = the lowest salary LAST YEAR Let $40,000 = the highest salary LAST YEAR This satisfies the condition that the range LAST YEAR = $30,000 If the annual salary of each of the 100 employees this ...”
February 21, 2019
Brent@GMATPrepNow posted a reply to The sum of two integers is 27. The larger integer is 25% in the Problem Solving forum
“Let x = the smaller integer So, 1.25x = the larger integer (since the larger integer is 25% greater than the smaller integer) The sum of two integers is 27. We can write: x + 1.25x = 27 Simplify: 2.25x = 27 Solve: x = 27/2.25 IMPORTANT: What''s a nice fast way to evaluate 27/2.25? An easy ...”
February 21, 2019
Brent@GMATPrepNow posted a reply to What is the greatest positive three-digit number that is div in the Problem Solving forum
“One approach is to check each answer choice, beginning with the largest answer choice E. 840 840 is divisible by 2, 3, 4, 5, 6 and 7 Answer: E Cheers, Brent”
February 21, 2019
Brent@GMATPrepNow posted a reply to What is the largest digit n for which the number 123,45n is in the Problem Solving forum
“RULE: if the SUM of the digits of a number is divisible by 3, then that number is divisible by 3 Take, for example, the number 1,001,226 1 + 0 + 0 + 1 + 2 + 2 + 6 = 12 Since 12 is divisible by 3, we know that 1,001,226 is divisible by 3 If 123,45n is divisible by 3, then 1 + 2 + 3 + 4 + 5 + n ...”
February 21, 2019
Brent@GMATPrepNow posted a reply to In the figure above, the angle marked at c has been created in the Data Sufficiency forum
“Target question: What is the sum of a, b, and c? This is a good candidate for rephrasing the target question. Since angles on a line add to 180°, we already know that b + c = 180 We get: a + b + c = a + 180 So, in order to find the sum of a, b and c, we need only find the value of a ...”
February 21, 2019
Brent@GMATPrepNow posted a reply to At a certain committee meeting only associate professors and in the Problem Solving forum
“Notice that the question asks us to find that TOTAL number of people present. In other words, it the question does NOT ask us to find the number of associate professors or assistant professors present. Since each person brings THREE items, and since total of 21 items were brought (10 pencils ...”
February 21, 2019
Brent@GMATPrepNow posted a reply to In a class of 30 students, 2 students did not borrow any in the Problem Solving forum
“The average (arithmetic mean) number of book borrowed per student was 2. Since there are 30 students altogether, the total number of borrowed books = (2)(30) = 60 2 students borrowed 0 books: total of 0 books 12 students borrowed 1 book each: total of 12 books 10 students borrowed 2 books ...”
February 21, 2019
Brent@GMATPrepNow posted a reply to If there are more than two numbers in a certain list, is in the Data Sufficiency forum
“Target question: Is each of the numbers n the list equal to zero? Given: There are more than 2 numbers in the list Statement 1: The product of any 2 numbers in the list is ZERO There are several possible sets that satisfy this condition. Here are two: Case a: the set is {0, 0, 0} in ...”
February 21, 2019
Max@Math Revolution posted a new topic called What is the greatest positive three-digit number that is div in the Problem Solving forum
“[GMAT math practice question] What is the greatest positive three-digit number that is divisible by 2, 3, 4, 5, 6 and 7? A. 120 B. 140 C. 210 D. 420 E. 840”
February 21, 2019
Max@Math Revolution posted a reply to A box contains 1 red ball, 3 green balls, 5 yellow balls, 7 in the Problem Solving forum
“=> The maximum number of draws without 7 balls of a single color is 1 + 3 + 5 + 6 + 6 + 6 = 27, obtained by drawing 1 red ball, 3 green balls, 5 yellow balls, 6 blue balls, 6 white balls and 6 black balls. If we draw one more ball, then we must have 7 balls of one color. Thus, we need to draw ...”
February 21, 2019
Max@Math Revolution posted a new topic called f(x)=x^{2n}+x^n+1, where n is an integer. Is f(x)=1? in the Data Sufficiency forum
“[GMAT math practice question] f(x)=x^{2n}+x^n+1, where n is an integer. Is f(x)=1? 1) x=-1 2) n is a multiple of 5.”
February 21, 2019
Max@Math Revolution posted a reply to If the median of 5 positive integers is 10, is their average in the Data Sufficiency forum
“=> Forget conventional ways of solving math questions. For DS problems, the VA (Variable Approach) method is the quickest and easiest way to find the answer without actually solving the problem. Remember that equal numbers of variables and independent equations ensure a solution. The first ...”
February 21, 2019
Max@Math Revolution posted a new topic called [Math Revolution] Practice “Math Questions of the Day” in the GMAT Math forum
“To help you sharpen your math skills and hit your target score of Q49-51, we are sending you 4 math questions (2 DS, 2 PS) and solutions regularly. These questions are the types of questions appearing in GMAT exam frequently. Please Click the link for solutions. ...”
February 21, 2019
Max@Math Revolution posted a new topic called What is the largest digit n for which the number 123,45n is in the Problem Solving forum
“[GMAT math practice question] What is the largest digit n for which the number 123,45n is divisible by 3? A. 3 B. 5 C. 6 D. 7 E. 9”
February 21, 2019
Max@Math Revolution posted a reply to The squares of two consecutive positive integers differ by 5 in the Problem Solving forum
“=> Let the two consecutive positive integers be n and n+1. Then (n+1)^2 – n^2 = 55, so 2n+1 = 55. It follows that 2n = 54 and n = 27. Therefore, the answer is A. Answer: A ”
February 21, 2019
Max@Math Revolution posted a new topic called If a and b are positive integers, is a+b divisible by 7? in the Data Sufficiency forum
“[GMAT math practice question] If a and b are positive integers, is a+b divisible by 7? 1) a – b is divisible by 7 2) a+b+7 is divisible by 91”
February 21, 2019
Max@Math Revolution posted a reply to If a and b are integers, and x and y are positive integers, in the Data Sufficiency forum
“=> Forget conventional ways of solving math questions. For DS problems, the VA (Variable Approach) method is the quickest and easiest way to find the answer without actually solving the problem. Remember that equal numbers of variables and independent equations ensure a solution. Since we ...”
February 21, 2019
Brent@GMATPrepNow posted a reply to Is mn < 10? in the Data Sufficiency forum
“Target question: Is mn < 10? Statement 1: m < 5 and n < 2 Let''s TEST some values. There are several values of m and n that satisfy statement 1. Here are two: Case a: m = 0 and n = 0. In this case mn = (0)(0) = 0. So, the answer to the target question is YES, mn IS less than 10 ...”
February 20, 2019
Brent@GMATPrepNow posted a reply to Bite-sized video lessons from GMAT Prep Now in the GMAT Math forum
“Data Sufficiency lesson #4: GMAT Data Sufficiency Strategies - Part I Video : https://www.youtube.com/watch?v=Ep09hi1OJpI Cheers, Brent”
February 20, 2019
Brent@GMATPrepNow posted a reply to John takes 15 hours to complete a certain job, while Bill ta in the Problem Solving forum
“Let''s first see what happens if Steven works as fast as possible. Since Bill can complete the job in 6 hours, Steven must complete the job in a little more than 6 hours. For example, we COULD see what happens if Steven takes 6.000000000000001 hours to complete the job. Unfortunately, ...”
February 20, 2019
Brent@GMATPrepNow posted a reply to If x, y, and z are three-digit positive integers and if x = in the Data Sufficiency forum
“Target question: Is the hundreds digit of x equal to the sum of the hundreds digits of y and z ? Notice that there are essentially 3 ways for the hundreds digit of x to be different from the sum of the hundreds digits of y and z Scenario #1: the hundreds digits of y and z add to more than 9. ...”
February 20, 2019
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, including by TESTing THE ANSWERS. Since we''re dealing with two lines - and we now that the two lines intersect - ...”
February 19, 2019
Rich.C@EMPOWERgmat.com posted a reply to A certain taxi company charges $3.10 for the first 1/5 of in the Problem Solving forum
“Hi All, We''re told that a certain taxi company charges $3.10 for the first 1/5 of a mile plus $0.40 for each additional 1/5 of a mile. We''re asked for the total charge for a taxi ride that was 8 miles long? The prompt gives us the price per 1/5 of a mile for a taxi ride. It''s worth noting ...”
February 19, 2019
Rich.C@EMPOWERgmat.com posted a reply to George bought a large electronic item with a 15% off coupon in the Problem Solving forum
“Hi All, We''re told that George bought a large electronic item with a 15% off coupon and paid a total bill. When he got outside, he studied the receipt and realize that he mistakenly had been given DOUBLE the discount of the coupon, even though there was no double-coupon offer in effect that ...”
February 19, 2019
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, ...”
February 19, 2019
Brent@GMATPrepNow posted a reply to Is x-y+1 greater than x+y-1 ? in the Data Sufficiency forum
“Target question: Is x - y + 1 > x + y - 1 ? This is a good candidate for rephrasing the target question. Take: x - y + 1 > x + y - 1 Subtract x from both sides to get: -y + 1 > y - 1 Add y to both sides to get: 1 > 2y - 1 Add 1 to both sides to get: 2 > 2y Divide both ...”
February 19, 2019
Brent@GMATPrepNow posted a reply to Anna has to visit at least 2 European cities on her vacation in the Problem Solving forum
“We need to consider 3 different cases: i) Anna visits 2 cities ii) Anna visits 3 cities iii) Anna visits 4 cities i) Anna visits 2 cities There are 4 options for the FIRST city and 3 options for the SECOND city So, the total number of 2-city itineraries = (4)(3) = 12 ii) Anna visits 3 ...”
February 19, 2019
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 ...”
February 19, 2019
Max@Math Revolution posted a new topic called A box contains 1 red ball, 3 green balls, 5 yellow balls, 7 in the Problem Solving forum
“[GMAT math practice question] A box contains 1 red ball, 3 green balls, 5 yellow balls, 7 blue balls, 9 white balls, and 11 black balls. What is the minimum number of balls that must be drawn from the box without replacement to guarantee that at least 7 balls of the same color are drawn? A. 7 ...”
February 19, 2019
Max@Math Revolution posted a new topic called If the median of 5 positive integers is 10, is their average in the Data Sufficiency forum
“[GMAT math practice question] If the median of 5 positive integers is 10, is their average (arithmetic mean) greater than 10? 1) The largest number is 40 2) The smallest number is 1”
February 19, 2019
Brent@GMATPrepNow posted a reply to How many positive perfect cubes are divisors of 4^6? in the Problem Solving forum
“4⁶ = (2²)⁶ = 2¹² Since 2¹² = (2³)(2⁹), we know 2³ is a divisor of 2¹² Since 2¹² = (2⁶)(2⁶), we know 2⁶ is a divisor of 2¹² Since 2¹² = (2⁹)(2³), we know 2⁹ is a divisor of 2¹² Since 2¹² = (2¹²)(2⁰), we know 2¹² is a divisor of 2¹² Since 2¹² = ...”
February 18, 2019
Brent@GMATPrepNow posted a reply to The squares of two consecutive positive integers differ by 5 in the Problem Solving forum
“Let x = the smaller integer So, x+1 = the larger integer (since the numbers are CONSECUTIVE) The squares of two consecutive positive integers differ by 55. We can write: (x + 1)² - x² = 55 Expand: x² + 2x + 1 - x² = 55 Simplify: 2x + 1 = 55 So: 2x = 54 Solve: x = 54/2 = 27 Answer: ...”
February 18, 2019
Max@Math Revolution posted a new topic called The squares of two consecutive positive integers differ by 5 in the Problem Solving forum
“[GMAT math practice question] The squares of two consecutive positive integers differ by 55. What is the smaller of the two integers? A. 27 B. 29 C. 30 D. 32 E. 35”
February 18, 2019
Max@Math Revolution posted a new topic called If a and b are integers, and x and y are positive integers, in the Data Sufficiency forum
“[GMAT math practice question] If a and b are integers, and x and y are positive integers, is a^x+b^y > 0? 1) a^{x+y}>0 2) b^{x+y}>0”
February 18, 2019
Max@Math Revolution posted a reply to What is the value of (2^{2020} + 2^{2018}) / (2^{2020}-2^{20 in the Problem Solving forum
“=> (2^{2020} + 2^{2018}) / (2^{2020}-2^{2018}) = (2^22^{2018} + 2^{2018}) / (2^22^{2018}-2^{2018}) = (2^{2018})(2^2+1) / (2^{2018})(2^2-1) = (2^2+1) / (2^2-1) = 5/3 Therefore, the answer is B. Answer: B”
February 18, 2019
Max@Math Revolution posted a reply to Which of the following expressions is equal to 2^32-2^31-2^3 in the Problem Solving forum
“=> 2^{32}-2^{31}-2^{30}? = (2^2)(2^{30})- (2^1)(2^{30})-2^{30} = 4(2^{30})- 2(2^{30})-2^{30} = (4-2-1)(2^{30}) =1(2^{30})=2^{30} Therefore, the answer is C. Answer: C”
February 18, 2019
Max@Math Revolution posted a reply to a^n^2+n-1/^a(n-1)(n+2)=? in the Data Sufficiency forum
“=> Forget conventional ways of solving math questions. For DS problems, the VA (Variable Approach) method is the quickest and easiest way to find the answer without actually solving the problem. Remember that equal numbers of variables and independent equations ensure a solution. The first ...”
February 18, 2019
Max@Math Revolution posted a reply to Is |a|<1? in the Data Sufficiency forum
“=> Forget conventional ways of solving math questions. For DS problems, the VA (Variable Approach) method is the quickest and easiest way to find the answer without actually solving the problem. Remember that equal numbers of variables and independent equations ensure a solution. The first ...”
February 18, 2019
Brent@GMATPrepNow posted a reply to A scientist has 400 units of a 6% phosphoric acid solution, in the Problem Solving forum
“We can solve this question with the weighted averages formula: Weighted average of groups combined = (group A proportion)(group A average) + (group B proportion)(group B average) + (group C proportion)(group C average) + ... Let x = the number of units of 12% phosphoric acid solution needed ...”
February 16, 2019
Brent@GMATPrepNow posted a reply to If a = 15! + 13, which of the following are factors of a? I in the Problem Solving forum
“Here''s a similar question to practice with: https://www.beatthegmat.com/divisibility-t111432.html Cheers, Brent”
February 16, 2019
Brent@GMATPrepNow posted a reply to Phone plan A charges $1.25 for the first minute and $0.15 in the Problem Solving forum
“Phone plan A charges $1.25 for the first minute and $0.15 for every minute thereafter. Let x = total duration of phone call (in minutes) So, the cost of an x-minute call = $1.25 + ($0.15)(x - 1) ASIDE: I created the expression ($0.15)(x - 1) because we pay $1.25 for the FIRST minute. So, if x = ...”
February 16, 2019
Brent@GMATPrepNow posted a reply to A magician has five animals in his magic hat: 3 doves and 2 in the Problem Solving forum
“Let''s apply probability rules First notice that, to get a matched pair, we can select 2 doves or 2 rabbits. So, P(matched pair) = P(1st pick is rabbit AND 2nd pick is rabbit OR 1st pick is dove AND 2nd pick is dove) We can now apply our AND and OR rules to get: P(matched pair) = x P(2nd ...”
February 16, 2019
Rich.C@EMPOWERgmat.com posted a reply to Working at their individual same constant rate, 24 machines in the Problem Solving forum
“Hi All, We''re told that while working at their individual same constant rate, 24 machines can complete a certain production job in 10 hours when they all work together. However, on a certain day, due to minor malfunction, 8 of those machines were not operating for the first 2 hours. We''re ...”
February 15, 2019
Rich.C@EMPOWERgmat.com posted a reply to If a positive integer q is divisible by both 3 and 11, then in the Problem Solving forum
“Hi All, We''re told that Q is a positive integer that is divisible by BOTH 3 and 11. We''re asked which of the following MUST also divisible evenly into Q. This question can be approached in a couple of different ways, including by TESTing VALUES. With these types of prompts, it often helps ...”
February 15, 2019
Brent@GMATPrepNow posted a reply to If a positive integer q is divisible by both 3 and 11, then in the Problem Solving forum
“I. 14 14 is NOT divisible by 3 or 11 So, statement I is NOT true. ELIMINATE A and D III. 66 Integer q COULD equal 33 (which is divisible by 3 and 11) Since 33 is NOT divisible by 66, statement III is NOT true. ELIMINATE C and E By the process of elimination, the correct answer is B ...”
February 15, 2019
Brent@GMATPrepNow posted a reply to Kevin buys beer in bottles and cans. He pays $1.00 for each in the Data Sufficiency forum
“Target question: How many bottles of beer did Kevin buy? Given: Kevin pays $1.00 for each can of beer and $1.50 for each bottle of beer. Kevin buys a total of 15 bottles and cans of beer Let C = the NUMBER of Cans that Kevin bought Let B = the NUMBER of Bottles that Kevin bought So, we can ...”
February 15, 2019
Max@Math Revolution posted a new topic called What is the value of (2^{2020} + 2^{2018}) / (2^{2020}-2^{20 in the Problem Solving forum
“[GMAT math practice question] What is the value of (2^{2020} + 2^{2018}) / (2^{2020}-2^{2018})? A. 3/5 B. 5/3 C. 2^{2018} D. 2^{2019} E. 2^{2020}”
February 15, 2019
Max@Math Revolution posted a reply to How many integers between 18 and 3399 are multiples of 17? in the Problem Solving forum
“=> 18 = 17*1 + 1, 34 = 17*2 is the least multiple of 17 greater than 18. 3399 = 17*199 + 16, 3383 = 17*199 is the greatest multiple of 17 less than 3399. Thus, the multiples of 17 between 18 and 3399 are 34=17*2, … , 3383 = 17*199. There are 198 = (199 – 2) + 1 of these numbers as they ...”
February 15, 2019
Max@Math Revolution posted a new topic called a^n^2+n-1/^a(n-1)(n+2)=? in the Data Sufficiency forum
“[GMAT math practice question] $$\frac{a^{n^2+n-1}}{a^{\left(n-1\right)\left(n+2\right)}}=?$$ 1) n=5 2) a=5”
February 15, 2019
Max@Math Revolution posted a reply to x^3-y^3=? in the Data Sufficiency forum
“=> Forget conventional ways of solving math questions. For DS problems, the VA (Variable Approach) method is the quickest and easiest way to find the answer without actually solving the problem. Remember that equal numbers of variables and independent equations ensure a solution. The first ...”
February 15, 2019
Brent@GMATPrepNow posted a reply to A group of x people is practicing levitation yoga. One-fourt in the Problem Solving forum
“ One-fourth of the people rise up in the air If 1/4 of the x people are in the AIR, the remaining 3/4 of the x people are on the GROUND So, (3/4)x = number of people on the GROUND After a while, 3 of them come back down. So, the number of people on the GROUND is increased by 3 So, now ...”
February 14, 2019
Brent@GMATPrepNow posted a reply to In the figure above, polygon N has been partially covered by in the Data Sufficiency forum
“Target question: How many sides does N have? Statement 1: x + y = 45 Since all angles in a triangle add to 180°, we know that the missing angle is 135° https://i.imgur.com/oUCDRTN.png There are plenty of polygons that have at least one angle measuring 135°. Here are two: Case a: ...”
February 14, 2019
Brent@GMATPrepNow posted a reply to Which of the following expressions is equal to 2^32-2^31-2^3 in the Problem Solving forum
“2^32 - 2^31 - 2^30 = (2^30)(2^2 - 2^1 - 1) = (2^30)(4 - 2 - 1) = (2^30)(1) = 2^30 Answer: C Cheers, Brent”
February 14, 2019
Max@Math Revolution posted a new topic called Which of the following expressions is equal to 2^32-2^31-2^3 in the Problem Solving forum
“[GMAT math practice question] Which of the following expressions is equal to 2^32-2^31-2^30? A. 3*2^29 B. 5*2^29 C. 2^30 D. 3*2^30 E. 2^31”
February 14, 2019
Max@Math Revolution posted a reply to How many numbers between 1 and 200, inclusive, have a 2 in in the Problem Solving forum
“=> In order for a number with 2 in the units place to be divisible by 4, the last two digits must be one of 12, 32, 52, 72 and 92. Thus, the numbers between 1 and 200, inclusive, satisfying this property are 12, 32, 52, 72, 92, 112, 132, 152 and 172. There are 8 such numbers. Therefore, ...”
February 14, 2019
Max@Math Revolution posted a new topic called Is |a|<1? in the Data Sufficiency forum
“[GMAT math practice question] Is |a|<1? 1) a^2 < 1 2) 1/(1-a^2) > 0”
February 14, 2019
Max@Math Revolution posted a reply to Is 3(a-b)>0? in the Data Sufficiency forum
“=> Forget conventional ways of solving math questions. For DS problems, the VA (Variable Approach) method is the quickest and easiest way to find the answer without actually solving the problem. Remember that equal numbers of variables and independent equations ensure a solution. The first ...”
February 14, 2019
Max@Math Revolution posted a new topic called [Math Revolution] Practice “Math Questions of the Day” in the GMAT Math forum
“To help you sharpen your math skills and hit your target score of Q49-51, we are sending you 4 math questions (2 DS, 2 PS) and solutions regularly. These questions are the types of questions appearing in GMAT exam frequently. Please Click the link for solutions. ...”
February 14, 2019
Brent@GMATPrepNow posted a reply to OG L-shaped garden in the Data Sufficiency forum
“Target question: What is the value of k? Statement 1: The area of the garden is 189 square feet. Let''s drawn an auxiliary line that divides the shape into two rectangular regions A and B. https://i.imgur.com/hJBOxsO.png Regions A and B have the following measurements. ...”
February 13, 2019
Brent@GMATPrepNow posted a reply to How many integers between 18 and 3399 are multiples of 17? in the Problem Solving forum
“Let''s list the multiples of 17 that are between 18 and 3399 : 34 = 2(17) 51 = 3(17) 68 = 4(17) 85 = 5(17) . . . 3383 = 199(17) So, the number of multiples of 17 is EQUAL to the number of integers from 2 to 199 inclusive ASIDE: A nice rule says: the number of integers from x to y ...”
February 13, 2019
Brent@GMATPrepNow posted a reply to A mountain resort will hold its annual one-day snowboarding in the Problem Solving forum
“GIVEN: P(snow) = 0.7, so P(no snow) = 0.3 Let''s use the complement to solve this. That is, P(event is held) = 1 - P(event is NOT held) P(event is NOT held) = P(no snow on Saturday AND no snow on Sunday) = P(no snow on Saturday) x P(no snow on Sunday) = 0.3 x 0.3 = 0.09 So, P(event is ...”
February 13, 2019
Max@Math Revolution posted a new topic called How many integers between 18 and 3399 are multiples of 17? in the Problem Solving forum
“[GMAT math practice question] How many integers between 18 and 3399 are multiples of 17? A. 198 B. 199 C. 200 D. 201 E. 202”
February 13, 2019
Max@Math Revolution posted a reply to If x=0.2, then what is the value of x^3-1/x-1? in the Problem Solving forum
“=> $$\frac{x^3-1}{x-1}=\frac{\left(x-1\right)\left(x^2+x+1\right)}{x-1}=x^2+x+1$$ Plugging in x = 0.2 yields x^2+x+1 = (0.2)^2 + (0.2) + 1 = 0.04 + 0.2 + 1 = 1.24 Therefore, the answer is C. Answer: C”
February 13, 2019
Max@Math Revolution posted a new topic called x^3-y^3=? in the Data Sufficiency forum
“[GMAT math practice question] x^3-y^3=? 1) x-y=0 2) |x|=|y|”
February 13, 2019
Max@Math Revolution posted a reply to What is the area of a right triangle? in the Data Sufficiency forum
“=> Forget conventional ways of solving math questions. For DS problems, the VA (Variable Approach) method is the quickest and easiest way to find the answer without actually solving the problem. Remember that equal numbers of variables and independent equations ensure a solution. Since ...”
February 13, 2019
Brent@GMATPrepNow posted a reply to The product P of two prime numbers is between 9 and 55. in the Problem Solving forum
“Prime numbers that are greater than 2 but less than 6: 3, 5 Prime numbers that are greater than 13 but less than 25: 17, 19, 23 Scan the answer choices . . . E) 51 = 3 x 17 PERFECT! Answer: E Cheers, Brent”
February 12, 2019
Brent@GMATPrepNow posted a reply to What is the probability that you get a pair when picking the in the Problem Solving forum
“P(select pair) = P(1st card is ANY card AND 2nd card matches 1st card) = P(1st card is ANY card) x P(2nd card matches 1st card) = 1 x 3/51 = 3/51 = 1/17 = C Aside: P(2nd card matches 1st card) = 3/51, because once 1 card is selected, there are 51 cards remaining in the deck. Among those 51 ...”
February 12, 2019
Brent@GMATPrepNow posted a reply to At her current job, Mary gets a 1.5% raise twice per year. in the Problem Solving forum
“One approach here is to apply the COMPOUND INTEREST formula. However, if you didn''t see that the question is analogous to a COMPOUND INTEREST question, we can also solve the question by looking for a pattern. Let''s try that: Time elapsed (in years) | salary 0 | s 0.5 | (1.015)(s) 1 | ...”
February 12, 2019
Brent@GMATPrepNow posted a reply to Of the 3,000 cars manufactured in Factory Q last year, how in the Data Sufficiency forum
“Target question: Of the 3,000 cars manufactured in Factory Q LAST YEAR, how many were still in operation at the end of the year? Neither statement provides any information about the cars manufactured LAST YEAR. Instead, we''re told about ALL of the cars ever manufactured . As such, the ...”
February 12, 2019
Brent@GMATPrepNow posted a reply to In the figure given, x = 3(y-z). What is the value of x? in the Problem Solving forum
“Since angles on a LINE add to 180°, . . . https://i.imgur.com/kAdhC7N.png . . . we know that x + z = 180 Subtract x from both sides to get: z = 180 - x Since angles in a CIRCLE add to 360°. . . https://i.imgur.com/l1SKqw5.png . . . we know that 60 + (180 - x) + y = 360 Simplify left ...”
February 12, 2019
Brent@GMATPrepNow posted a reply to In the xy-coordinate plane, if the point (0,2) lies on the g in the Problem Solving forum
“KEY CONCEPT: In order for a point to be ON a line, the x- and y-coordinates of the point must satisfy the equation of that line So, for example, the point (3,7) lies ON the line defined by the equation y = 2x + 1, because x = 3 and y = 7 satisfy the equation y = 2x + 1 That is, 7 = 2(3) + 1 ...”
February 12, 2019
Brent@GMATPrepNow posted a reply to Set S consists of n consecutive integers, where n > 1. in the Data Sufficiency forum
“ Given: Set S consists of n consecutive integers, where n > 1. Target question: What is the value of n? IMPORTANT: Notice that the two statements are VERY SIMILAR. That is, if the sum of the values is 14 (statement 2), then it is guaranteed that the sum is divisible by 7 (statement 1). ...”
February 12, 2019
Max@Math Revolution posted a new topic called How many numbers between 1 and 200, inclusive, have a 2 in in the Problem Solving forum
“[GMAT math practice question] How many numbers between 1 and 200, inclusive, have a 2 in the units place and are divisible by 4? A. 8 B. 9 C. 10 D. 11 E. 12”
February 12, 2019
Max@Math Revolution posted a new topic called Is 3(a-b)>0? in the Data Sufficiency forum
“[GMAT math practice question] Is 3(a-b) > 0? 1) a^3 > b^3 2) a > b”
February 12, 2019
Brent@GMATPrepNow posted a reply to A computer chip manufacturer expects the ratio of the number in the Problem Solving forum
“Let''s find some TOTALS for all 4 shipments combined. There are 51,000 chips altogether There are 17 defective chips altogether. So, 17/51000 of the chips are defective. (notice that 17 divides nicely into 51000!) SIMPLIFY: 1/3000 of the chips are defective So, if we have a shipment of ...”
February 11, 2019
Brent@GMATPrepNow posted a reply to If O is the center of the circle with diameter AB and T is a in the Problem Solving forum
“Since angles in a triangle add to 180°, we know that the missing angle = (90 - 2x)° https://i.imgur.com/FcSiZi2.png Aside: Notice that (90 - 2x)° + 90° + 2x° =180° Since angles on a line add to 180°, we know that the missing angle = (90 + 2x)° https://i.imgur.com/9Z5ULFo.png ...”
February 11, 2019
Brent@GMATPrepNow posted a reply to tough geo. problem in the Data Sufficiency forum
“Target question: What is the length of side BC? Statement 1: Line segment AD has length 6. BEFORE we deal with statement 1, let''s see what information we can add to the diagram. For example, since ∆BDC has 2 equal angles (of 2x°), we know that side BD = side BC: ...”
February 11, 2019
Brent@GMATPrepNow posted a reply to What is the area of a right triangle? in the Data Sufficiency forum
“Target question: What is the area of a right triangle? Statement 1: The length of one side is 3 Knowing the length of only 1 side will not help us answer the target question with certainty. Statement 1 is NOT SUFFICIENT Statement 2: The length of one side is 4 NOT SUFFICIENT (same ...”
February 11, 2019
Brent@GMATPrepNow posted a reply to If x=0.2, then what is the value of x^3-1/x-1? in the Problem Solving forum
“Some spaces and/or brackets would definitely help here. Do you mean x^3 - 1/x - 1 or x^3 - 1/(x - 1) or (x^3 - 1)/(x - 1)?? Cheers, Brent”
February 11, 2019
Brent@GMATPrepNow posted a reply to If n and p are integers, is p > 0? in the Data Sufficiency forum
“ Given: n and p are integers Target question: Is p > 0? Statement 1: n + 1 > 0 No information about p. Statement 1 is NOT SUFFICIENT Statement 2: np > 0 There are several values of n and p that satisfy statement 2. Here are two: Case a: n = 1 and p = 1. In this case, ...”
February 11, 2019
Max@Math Revolution posted a new topic called If x=0.2, then what is the value of x^3-1/x-1? in the Problem Solving forum
“[GMAT math practice question] If x=0.2, then what is the value of x^3-1/x-1? A. 1.2 B. 1.22 C. 1.24 D. 1.44 E. 2.22”
February 11, 2019
Max@Math Revolution posted a new topic called What is the area of a right triangle? in the Data Sufficiency forum
“[GMAT math practice question] What is the area of a right triangle? 1) The length of one side is 3 2) The length of one side is 4”
February 11, 2019
Max@Math Revolution posted a reply to a0 = 0, a1 = 1. an is the remainder when an-1 + an-2 is divi in the Problem Solving forum
“=> a0 = 0 a1 = 1 a2 = a1 + a0 = 1 + 0 = 1 a3 = a_2 + a1 = 1 + 1 = 2 a4 = 0 since a3 + a2 = 2 + 1 = 3 = 3(1)+0, and the remainder when a3 + a2 is divided by 3 is zero. a5 = a4 + a3 = 0 + 2 = 2 a6 = a5 + a4 = 2 + 0 = 2 a7 = 1 since a6 + a5 = 2 + 2 = 4= 3(1)+1, and the remainder when a6 + ...”
February 11, 2019
Max@Math Revolution posted a reply to What is the sum of the digits of the number (2^{2018})(5^{20 in the Problem Solving forum
“=> (2^{2018})(5^{2019})(3^2) = (2^{2018})(5^{2019})(5^1)(3^2) = (10^{2018})(5)(9) = (45)(10^{2018}) = 450000…0 The sum of the digits is 4 + 5 + 0 + 0 + 0 + … + 0 = 9 Therefore, the answer is E. Answer: E”
February 11, 2019
Max@Math Revolution posted a reply to Does f(x)=ax^4+bx^3+cx^2+dx+e have (x-2) as a factor? in the Data Sufficiency forum
“=> Forget conventional ways of solving math questions. For DS problems, the VA (Variable Approach) method is the quickest and easiest way to find the answer without actually solving the problem. Remember that equal numbers of variables and independent equations ensure a solution. The first ...”
February 11, 2019
Max@Math Revolution posted a reply to 3x+4y=? in the Data Sufficiency forum
“=> Forget conventional ways of solving math questions. For DS problems, the VA (Variable Approach) method is the quickest and easiest way to find the answer without actually solving the problem. Remember that equal numbers of variables and independent equations ensure a solution. The first ...”
February 11, 2019
Rich.C@EMPOWERgmat.com posted a reply to During the four years that Mrs. Lopez owned her car, she fou in the Problem Solving forum
“Hi All, We''re told that during the 4 years that Mrs. Lopez owned her car, she found that her total car expenses were $18,000. Fuel and maintenance costs accounted for 1/3 of the total and depreciation accounted for 3/5 of the REMAINDER. The cost of insurance was 3 times the cost of financing, ...”
February 10, 2019
Rich.C@EMPOWERgmat.com posted a reply to At Megalomania Industries, factory workers were paid $20 per in the Problem Solving forum
“Hi All, We''re told that at Megalomania Industries, factory workers were paid $20 per hour in 1990 and $10 per hour in 2000 and the CEO of Megalomania Industries was paid $5 million per year in 1990 and $50 million per year in 2000. We''re asked for what percent greater was the percent increase ...”
February 10, 2019
Rich.C@EMPOWERgmat.com posted a reply to A company’s four cars running 10 hrs a day consume 1200 lt in the Problem Solving forum
“Hi All, We''re told that a company’s 4 cars running 10 hrs a day consume 1200 liters of fuel in 10 days. In the next 6 days, the company will need to run 9 cars for 12 hrs each so it rents 5 more cars which consume 20% less fuel than the company’s four cars. We''re asked for the number of ...”
February 10, 2019
Brent@GMATPrepNow posted a reply to If x and y are integers, is x^2-y^2 odd? 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 x² - y² odd? IMPORTANT: Notice that we can factor x² - y² to get: x² - y² = (x + y)(x - y) ...”
February 10, 2019
Brent@GMATPrepNow posted a reply to In a group of 100 adults, 75 percent of the women are in the Problem Solving forum
“GIVEN: 75% women are LEFT handed This also tells us that 25% women are RIGHT handed GIVEN: There are 12 right-handed women Let W = total number of women in the group So, 25% of W = 12 Rewrite as: 0.25W = 12 Solve: W = 12/0.25 = 48 So, there are 48 women So, the number of men in the ...”
February 10, 2019
Brent@GMATPrepNow posted a reply to Triangle XYZ is an isosceles right triangle. If side XY is l in the Problem Solving forum
“Triangle XYZ is an isosceles right triangle. Let''s sketch an isosceles right triangle: https://i.imgur.com/N3UOppf.png Side XY is longer than side YZ Since the hypotenuse is the longest side of a right triangle, side XY must be the hypotenuse. Add this to our diagram: ...”
February 9, 2019
Rich.C@EMPOWERgmat.com posted a reply to 530 to 700 in 3 months- possible? best strategy/study plan? in the GMAT Strategy forum
“Hi mgec0424, To start, a 520 is a decent initial CAT Score (the average Score on the Official GMAT hovers around 550 most years). Scoring 530 on your second CAT isn''t necessary a ''bad'' thing either - since it takes time to properly use what you''ve learn and adapt your approach to the overall ...”
February 8, 2019
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 ...”
February 8, 2019
Brent@GMATPrepNow posted a reply to An electrical supplies store sells 140 power stabilizer in the Problem Solving forum
“Let x = the selling price per unit So, x - 16 = the PROFIT on ONE unit And 140(x - 16) = the PROFIT on the sale of 140 units (aka the weekly profit) What is the minimum selling price per unit that will ensure a weekly profit of at least $5600 from sales of power stabilizers? In other words, ...”
February 8, 2019
Brent@GMATPrepNow posted a reply to What is the remainder when the positive integer n is divided in the Data Sufficiency forum
“Target question: What is the remainder when the positive integer n is divided by 6? Statement 1: n is multiple of 5 Let''s TEST some values. There are several values of n that satisfy statement 1. Here are two: Case a: n = 10. In this case, the answer to the target question is the ...”
February 8, 2019
Max@Math Revolution posted a new topic called a0 = 0, a1 = 1. an is the remainder when an-1 + an-2 is divi in the Problem Solving forum
“0 = 0, a1 = 1. an is the remainder when an-1 + an-2 is divided by 3 for n ≥ 2. What is the value of a101 + a102 + a103 + a104 + a105 + a106 + a107 + a108? A. 0 B. 3 C. 5 D. 7 E. 9”
February 8, 2019
Max@Math Revolution posted a reply to We define the harmonic mean of a set of numbers as the recip in the Problem Solving forum
“=> 1 / { ( 1/20 + 1/30 ) / 2 } = 1 / { ( 3/60 + 2/60 ) / 2 } = 1 / { (5/60) / 2 } = 1 / { 5 / 120 } = 120 / 5 = 24. Therefore, the answer is B. Answer: B”
February 8, 2019
Max@Math Revolution posted a new topic called Does f(x)=ax^4+bx^3+cx^2+dx+e have (x-2) as a factor? in the Data Sufficiency forum
“[GMAT math practice question] Does f(x)=ax^4+bx^3+cx^2+dx+e have (x-2) as a factor? 1) f(2)=0 2) f(-2)=0”
February 8, 2019
Max@Math Revolution posted a reply to If x, y, z are positive integers, is xyz ≥ 64? in the Data Sufficiency forum
“=> Forget conventional ways of solving math questions. For DS problems, the VA (Variable Approach) method is the quickest and easiest way to find the answer without actually solving the problem. Remember that equal numbers of variables and independent equations ensure a solution. Since we ...”
February 8, 2019
Brent@GMATPrepNow posted a reply to What is the sum of the digits of the number (2^{2018})(5^{20 in the Problem Solving forum
“Useful rule: (x^k)(y^k) = (xy)^k Example: (3^4)(7^4) = 21^4 (2^2018)(5^2019)(3^2) = (2^2018)((5^2018)(5^1))(3^2) = (2^2018)(5^2018)(5^1))(3^2) = (10^2018)(5^1))(3^2) = (10^2018)(5)(9) = (10^2018)(45) We know that (10^2018) = 1 followed by 2018 zeros So, (10^2018)(45) = 45 followed by ...”
February 7, 2019
Brent@GMATPrepNow posted a reply to If a and b are integers, is a + b + 3 an odd integer? (1) in the Data Sufficiency forum
“Target question: Is a + b + 3 an odd integer? Given: a and b are integers Statement 1: ab is an odd integer. Some useful rules: 1. ODD - ODD = EVEN 2. ODD - EVEN = ODD 3. EVEN - ODD = ODD 4. EVEN - EVEN = EVEN 5. (ODD)(ODD) = ODD 6. (ODD)(EVEN) = EVEN 7. (EVEN)(EVEN) = EVEN ...”
February 7, 2019
Brent@GMATPrepNow posted a reply to The sides of a right triangle are consecutive even integers, in the Problem Solving forum
“GIVEN: p = length of the longest side Since the side lengths are consecutive even integers, we can say: p - 2 = length of the 2nd longest side p - 4 = length of the shortest side NOTE: The longest side is the HYPOTENUSE. So, p = length of the HYPOTENUSE And p - 2 = length of one leg of ...”
February 7, 2019
Brent@GMATPrepNow posted a reply to In the diagram above, O is the center of the circle. What is in the Data Sufficiency forum
“Target question: What is the length of chord AC? Given: O is the center of the circle If O is the center of the circle, then AB is the circle''s DIAMETER If AB is the DIAMETER, then ∠C = 90°, because ∠C is an inscribed angle containing ("holding") the diameter. So, let''s ...”
February 7, 2019
Rich.C@EMPOWERgmat.com posted a reply to Ten telegenic contestants with a variety of personality diso in the Problem Solving forum
“Hi All, For Test Takers who know the Combination Formula, this question is a fairly straight-forward prompt. If you DON''T know the Combination Formula though, then here''s what it is and how to use it. Any time a prompt asks for "groups" or "combinations" of things, then the ...”
February 7, 2019
Rich.C@EMPOWERgmat.com posted a reply to The sides of a right triangle are consecutive even integers, in the Problem Solving forum
“Hi All, We''re told that the sides of a right triangle are CONSECUTIVE EVEN INTEGERS, and the length of the LONGEST side is P. We''re asked which of the following equations could be used to find P. This question can be solved in a couple of different ways, including by TESTing VALUES. To ...”
February 7, 2019
Rich.C@EMPOWERgmat.com posted a reply to There are 13 hearts in a full deck of 52 cards. In a certain in the Problem Solving forum
“Hi All, The probability of pulling a heart out of a full deck of cards is 13/52 = 1/4, so the probability of NOT pulling a heart out of a full deck = 1 - 1/4 = 3/4. The probability of pulling a heart on the THIRD try, and NOT pulling a heart on the first two tries is: (3/4)(3/4)(1/4) = ...”
February 7, 2019
Brent@GMATPrepNow posted a reply to Ten telegenic contestants with a variety of personality diso in the Problem Solving forum
“Let''s take the task of creating the teams and break it into stages. Stage 1: Select two 5 contestants to be in tribe A Since the order in which we select the contestants does not matter, we can use combinations. We can select 5 contestants from 10 contestants in 10C5 ways 10C5 = ...”
February 7, 2019
Max@Math Revolution posted a new topic called What is the sum of the digits of the number (2^{2018})(5^{20 in the Problem Solving forum
“[GMAT math practice question] What is the sum of the digits of the number (2^{2018})(5^{2019})(3^2)? A. 4 B. 5 C. 6 D. 7 E. 9”
February 7, 2019
Max@Math Revolution posted a reply to If (x-7)^2=-|y-5|, xy=? in the Problem Solving forum
“=> (x-7)^2=-|y-5| => (x-7)^2+|y-5| = 0 => x = 7 and y = 5 This yields xy = 35. Therefore, the answer is D. Answer: D”
February 7, 2019
Max@Math Revolution posted a new topic called 3x+4y=? in the Data Sufficiency forum
“[GMAT math practice question] 3x+4y=? 1) 2|x|+3|y|=0 2) 3|x|+2|y|=0”
February 7, 2019
Max@Math Revolution posted a reply to If a > b > c > d > 0, is d < 4? in the Data Sufficiency forum
“=> Forget conventional ways of solving math questions. For DS problems, the VA (Variable Approach) method is the quickest and easiest way to find the answer without actually solving the problem. Remember that equal numbers of variables and independent equations ensure a solution. The first ...”
February 7, 2019
Rich.C@EMPOWERgmat.com posted a reply to Starting with 0, a mathematician labels every non-negative i in the Problem Solving forum
“Hi All, We''re told that starting with 0, a mathematician labels every non-negative integer as one of five types: alpha, beta, gamma, delta, or epsilon, in that repeating order as the integers increase. For instance, the integer 8 is labeled delta. We''re asked for the label on an integer that ...”
February 7, 2019
Brent@GMATPrepNow posted a reply to We define the harmonic mean of a set of numbers as the recip in the Problem Solving forum
“What is the harmonic mean of 20 and 30? NOTE: 20 = 20/1 So, the reciprocal of 20 = 1/20 And the reciprocal of 30 = 1/30 The average of 1/20 and 1/30 = (1/20 + 1/30 )/2 = (3/60 + 2/60 )/2 = (5/60 )/2 = (5/60 )/(2/1) = (5/60 )(1/2) = 5/120 The reciprocal of 5/120 = 120/5 = 24 Answer: ...”
February 6, 2019
Max@Math Revolution posted a new topic called We define the harmonic mean of a set of numbers as the recip in the Problem Solving forum
“[GMAT math practice question] We define the harmonic mean of a set of numbers as the reciprocal of the average (arithmetic mean) of the reciprocals of the numbers. What is the harmonic mean of 20 and 30? A. 22 B. 24 C. 25 D. 26 E. 28”
February 6, 2019
Max@Math Revolution posted a reply to What is the number of the x-intercepts of y=x^4-3x^3+2x^2? in the Problem Solving forum
“=> y = x^4-3x^3+2x^2 => y = x^2(x^2-3x+2) => y = x^2(x-1)(z-2) The x-intercepts occur when y = 0. This occurs when x = 0, x = 1 and x = 2. There are three x-intercepts. Therefore, the answer is C. Answer: C”
February 6, 2019
Max@Math Revolution posted a new topic called If x, y, z are positive integers, is xyz ≥ 64? in the Data Sufficiency forum
“[GMAT math practice question] If x, y, z are positive integers, is xyz ≥ 64? 1) xy ≥ yz ≥ zx ≥ 16 2) x + y + z = 64”
February 6, 2019
Max@Math Revolution posted a reply to If x, y are integers, is (x-y)(x+y)(x^2+y^2) an odd number? in the Data Sufficiency forum
“=> Forget conventional ways of solving math questions. For DS problems, the VA (Variable Approach) method is the quickest and easiest way to find the answer without actually solving the problem. Remember that equal numbers of variables and independent equations ensure a solution. The first ...”
February 6, 2019
Brent@GMATPrepNow posted a reply to A certain bag contains red, blue, and green marbles. What is in the Data Sufficiency forum
“ Given: A certain bag contains red, blue, and green marbles. Let R = # number red marbles in the bag Let B = # number blue marbles in the bag Let G = # number green marbles in the bag Target question: What is the value of G/R? Statement 1: The number of blue marbles in the bag is two ...”
February 6, 2019
Brent@GMATPrepNow posted a reply to If x is a nonzero number, which of the three numbers x, 1/x in the Data Sufficiency forum
“ Given: x is a nonzero number Target question: Which of the three numbers x, 1/x and x² is greatest? Statement 1: -1 < x < 1 This statement doesn''t FEEL sufficient, so I''ll TEST some values. There are several values of x that satisfy statement 1. Here are two: Case a: x = ...”
February 6, 2019
Rich.C@EMPOWERgmat.com posted a reply to Three digits have been removed from each of the following in the Problem Solving forum
“Hi All, We''re told that three digits have been removed from each of the following numbers and n = 25. We''re asked which of the numbers is equal to 3*2^(n-1). To start, the fact that three digits have been removed from each answer is irrelevant. When a GMAT question presents information ...”
February 5, 2019
Rich.C@EMPOWERgmat.com posted a reply to The organizers of a conference offered a certain number of s in the Problem Solving forum
“Hi All, We''re told that the organizers of a conference offered a certain number of simultaneous seminars with the intention that each seminar would be attended by 18 conference attendees. However, space limitations allowed only up to 15 conference attendees to participate in each of a number of ...”
February 5, 2019
Rich.C@EMPOWERgmat.com posted a reply to At a school-wide athletic fair, five students won a combined in the Problem Solving forum
“Hi All, We''re told that at a school-wide athletic fair, five students won a combined total of 20 ribbons, each of the five students won AT LEAST one ribbon and NO two students won the SAME number of ribbons. We''re asked for the greatest number of ribbons that the student with the ...”
February 5, 2019
Rich.C@EMPOWERgmat.com posted a reply to In how many ways can a 4-letter word be formed from the in the Problem Solving forum
“Hi regor60, I agree that this prompt is poorly-worded. The "intent" is to ask for every 4-letter arrangement that fits the given restrictions, INCLUDING "words" that do not appear in the dictionary (re: arrangements that are not actually words). GMAT question-writers are far ...”
February 5, 2019
Rich.C@EMPOWERgmat.com posted a reply to In the coordinate plane, Line A has a slope of -1 and an in the Problem Solving forum
“Hi All, We''re told that in the coordinate plane, Line A has a slope of -1 and an x-intercept of 1 and Line B has a slope of 2 and a y-intercept of -2. The two lines intersect at the point (a,b). We''re asked for the sum a and b. When dealing with lines, it often helps to write the given ...”
February 5, 2019
Brent@GMATPrepNow posted a reply to Three sisters have an average (arithmetic mean) age of 25 in the Problem Solving forum
“If the average age is 25, we can write: (sum of all 3 ages)/3 = 25 This means, the sum of all 3 ages = 75 If the median is 24, then we can express the ages in ascending order as follows: __ , 24, __ Since the sum of the ages is 75, we can MINIMIZE the age of the oldest girl by MAXIMIZING the ...”
February 5, 2019
Max@Math Revolution posted a new topic called If (x-7)^2=-|y-5|, xy=? in the Problem Solving forum
“[GMAT math practice question] If (x-7)^2=-|y-5|, xy=? A. 5 B. 7 C. 12 D. 35 E. cannot be determined”
February 5, 2019
Max@Math Revolution posted a new topic called If a > b > c > d > 0, is d < 4? in the Data Sufficiency forum
“[GMAT math practice question] If a > b > c > d > 0, is d < 4? 1) 1/c + 1/d > 1/2 2) (1/a)+(1/b)+(1/c)+(1/d) = 1”
February 5, 2019
Brent@GMATPrepNow posted a reply to A contractor combined x tons of a gravel mixture that in the Data Sufficiency forum
“Let''s use some weighted averages to solve this question Weighted average of groups combined = (group A proportion)(group A average) + (group B proportion)(group B average) + (group C proportion)(group C average) + ... Target question: What is the value of x ? Given: A contractor combined x ...”
February 4, 2019
Rich.C@EMPOWERgmat.com posted a reply to Work/Rate problem in the Problem Solving forum
“Hi benjemin28, It''s worth noting that he Quant section of the GMAT is NOT a ''math test'' - it''s a ''critical thinking test'' that requires lots of little calculations as you work through it. Most GMAT questions are designed so that they can be solved in more than one way (and certain Tactics ...”
February 4, 2019
Rich.C@EMPOWERgmat.com posted a reply to In a certain sock drawer, there are 4 pairs of black socks, in the Problem Solving forum
“Hi All, The concept in these types of questions is based on the ''worst case scenario'' - to guarantee that something will happen, you have to focus on the ''extreme/longest'' way that it could happen. Here, we have 4 black socks, 3 gray socks and 2 orange socks. The question asks for the ...”
February 4, 2019
Rich.C@EMPOWERgmat.com posted a reply to The original price of a certain TV set is discounted by x in the Problem Solving forum
“Hi All, We''re told that the original price of a certain TV set is discounted by X percent, the reduced price is then discounted by 2X percent and P is the original price of the TV set. We''re asked which of the following represents the price of the television set after the two successive ...”
February 4, 2019
Brent@GMATPrepNow posted a reply to A committee of 6 is chosen from 8 men and 5 women so as to in the Problem Solving forum
“Since the committee must have 6 people, there are two cases that meet the given restrictions: 1) The committee has 2 men and 4 women 2) The committee has 3 men and 3 women 1) The committee has 2 men and 4 women Since the order in which we select the men and women does not matter, we can use ...”
February 4, 2019
Brent@GMATPrepNow posted a reply to Mixture problem unclear in the Problem Solving forum
“When solving mixture questions, I find it useful to sketch the solutions with the ingredients SEPARATED. Since we''re asked to find a PERCENTAGE, we can assign a "nice" value to the original volume. So, let''s say we start with 100 liters https://i.imgur.com/yt2KAw7.png As you can ...”
February 4, 2019
Brent@GMATPrepNow posted a reply to Mr. Jones spends $25 on movie tickets for a party of adults in the Data Sufficiency forum
“ Given: Mr. Jones spends $25 on movie tickets for a party of adults and children. Target question: How many children''s tickets did he buy? Statement 1: Adult movie tickets cost $3 each and children''s tickets cost $2 each. There are several scenarios that satisfy statement 1. Here are ...”
February 4, 2019
Brent@GMATPrepNow posted a reply to In a certain sock drawer, there are 4 pairs of black socks, in the Problem Solving forum
“If we remove 1 black sock, 1 gray sock, and 1 orange sock, then we still don''t have a matching sock. So, we can select 3 socks WITHOUT having a matching pair. However, if we pick ANY sock for our fourth sock, that sock MUST match one of the first 3 socks selected. Answer: A Cheers, Brent”
February 4, 2019
Max@Math Revolution posted a new topic called What is the number of the x-intercepts of y=x^4-3x^3+2x^2? in the Problem Solving forum
“[GMAT math practice question] What is the number of the x-intercepts of y=x^4-3x^3+2x^2? A. one B. two C. three D. four E. five”
February 4, 2019
Max@Math Revolution posted a reply to If ( x – y – 2 )^2 + ( x + z + 3 )^2 = 0, then what is t in the Problem Solving forum
“=> Since ( x – y – 2 )^2 + ( x + z + 3 )^2 = 0, we must have x – y – 2 = 0 and x + z + 3 = 0. So, x = y + 2 and x + z + 3 = ( y + 2 ) + z + 3 = y + z + 5 = 0. Thus, y + z = -5. Therefore, the answer is E. Answer: E”
February 4, 2019
Max@Math Revolution posted a reply to f(2x-1) = ( x + 2 ) / ( x – 2 ). What is f(x)? in the Problem Solving forum
“=> We solve this problem using a change of variable. Let t = 2x -1. Then 2x = t + 1 or x = ( t + 1 ) / 2. f(2x-1) = f(t) = ( (t+1)/2 + 2 ) / ( (t+1)/2 – 2 ) = ( t + 1 + 4 ) / ( t + 1 – 4 ) (after multiplying both top and bottom by 2) = ( t + 5 ) / ( t – 3 ). Making the substitution ...”
February 4, 2019
Max@Math Revolution posted a new topic called If x, y are integers, is (x-y)(x+y)(x^2+y^2) an odd number? in the Data Sufficiency forum
“[GMAT math practice question] If x, y are integers, is (x-y)(x+y)(x^2+y^2) an odd number? 1) x is an odd number 2) x-y is an odd number”
February 4, 2019
Max@Math Revolution posted a reply to If p, x, and y are integers, x^p/x^q=? in the Data Sufficiency forum
“=> Forget conventional ways of solving math questions. For DS problems, the VA (Variable Approach) method is the quickest and easiest way to find the answer without actually solving the problem. Remember that equal numbers of variables and independent equations ensure a solution. Since we ...”
February 4, 2019
Max@Math Revolution posted a reply to Is 3 a factor of x? in the Data Sufficiency forum
“=> Forget conventional ways of solving math questions. For DS problems, the VA (Variable Approach) method is the quickest and easiest way to find the answer without actually solving the problem. Remember that equal numbers of variables and independent equations ensure a solution. Since we ...”
February 4, 2019
Brent@GMATPrepNow posted a reply to Piper bought three shirts. The three shirts cost $210 in the Data Sufficiency forum
“IMPORTANT: Notice that statements 1 and 2 provide the EXACT SAME INFORMATION. When this occurs, the correct answer is either D or E Since the information is so sparse, I have a feeling that the correct answer is E. So, I''m going to try to find two possible cases that satisfy both statements, yet ...”
February 3, 2019
Brent@GMATPrepNow posted a reply to In the graduating class of a certain college, 48 percent of in the Problem Solving forum
“I thought I''d point out that Mitch''s Double Matrix Method 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 students, and the two characteristics are: - male or female - younger than 25 ...”
February 3, 2019
Brent@GMATPrepNow posted a reply to Bite-sized video lessons from GMAT Prep Now in the GMAT Math forum
“Data Sufficiency lesson #3: Avoiding Common Mistakes - Part I Video : https://www.youtube.com/watch?v=iACq36scVYQ Cheers, Brent”
February 3, 2019
Rich.C@EMPOWERgmat.com posted a reply to The value of (10^8-10^2)/(10^7-10^3) is closest to which in the Problem Solving forum
“Hi All, We''re asked to choose the answer that is CLOSEST in value to (10^8-10^2)/(10^7-10^3). While you might be tempted to try lots of ''math steps'', if you consider how the answer choices are written, you can use a bit of estimation and logic to get to the correct answer without doing too ...”
February 2, 2019
Rich.C@EMPOWERgmat.com posted a reply to A company produces baseball cards in equal numbers of regula in the Problem Solving forum
“Hi All, We''re told that a company produces baseball cards in EQUAL numbers of regular packs of 16 and deluxe packs of 30. On a certain day, the company produces 241 cards. We''re asked for the SMALLEST number of additional cards the company needs to produce in order to maintain its regular ...”
February 2, 2019
Rich.C@EMPOWERgmat.com posted a reply to If the probability of rain on any given day is 50%, what is in the Problem Solving forum
“Hi All, We''re told that the probability of rain on any given day is 50%. We''re asked for the probability that it will rain on AT LEAST three days in a ROW during a five-day period. This question can be approached in a number of different ways; you might find it easiest to do a little math and ...”
February 2, 2019
Rich.C@EMPOWERgmat.com posted a reply to Father John forms a choir from the church attendants. in the Problem Solving forum
“Hi All, We''re told that Father John forms a choir from the church attendants. 30 people attend John''s church and the choir has 28 spots available, with one person as the lead singer. We''re asked for the number of different combinations for the choir. This question involves the Combination ...”
February 2, 2019
Rich.C@EMPOWERgmat.com posted a reply to A scriptwriter charges $4 for every standard script, which in the Problem Solving forum
“Hi All, We''re told that a scriptwriter has a particular series of fees for a script (based on the length of the script). The scriptwriter charges.... 1) $4 for every standard script, which is 4 pages or shorter in length 2) 50 cents for every additional page 3) NO CHARGE for every 11th ...”
February 2, 2019
ceilidh.erickson posted a reply to If x and y are positive integers, what is the remainder when in the Data Sufficiency forum
“If x and y are positive integers, what is the remainder when 5^x is divided by y? In order to answer this question, we need some information about x and y. For some divisors of y, the value of x wouldn''t matter: if y = 5, the remainder is always 0, because any 5^x will be divisible by 5. If y = ...”
February 2, 2019
ceilidh.erickson posted a reply to On the number line, the distance between point A and point C in the Data Sufficiency forum
“With NUMBER LINE problems in DS, remember that information about distance alone does not give us information about direction. When unpacking the question, try to imagine different scenarios with the given information. Try to come up with one scenario in which C is between A and B, and one in ...”
February 2, 2019
ceilidh.erickson posted a reply to Beth has a collection of 8 boxes of clothing for a charity, in the Problem Solving forum
“When there are variables in the answer choices in a PS problem, it''s often easy to pick our own values for those variables. With averages, it''s often easiest to just treat each member of the group as the same. i.e. let''s say that in this case, we have 8 identical boxes with 12 clothing items ...”
February 2, 2019
ceilidh.erickson posted a reply to Is tutoring necessary for Verbal? in the GMAT Strategy forum
“In my opinion, no. Don''t get a tutor... yet. When students say "I don''t have much time, so I''ll get a tutor rather than studying on my own," that''s usually not a recipe for success. Tutoring is most productive when it''s supplementing significant time spent studying on your own. Tutors ...”
February 2, 2019
ceilidh.erickson posted a reply to Guidance on study plan in the GMAT Strategy forum
“Yes, this is more than enough material to get started with. Here''s what you should do: 1. Analyze the practice test you''ve taken in a lot of depth. Which areas were you weakest? Strongest? Fastest? Slowest? Decide which topics and question types need more of your time and attention. Be very ...”
February 2, 2019
Brent@GMATPrepNow posted a reply to Beth has a collection of 8 boxes of clothing for a charity, in the Problem Solving forum
“One box contains 12 items of clothing Let t, u, v, w, x, y, z = the number of items in each of the other 7 boxes Beth has a collection of 8 boxes of clothing for a charity, and the average (arithmetic mean) number of pieces of clothing per box is c. We can write: (t + u + v + w + x + y + z + ...”
February 2, 2019
Rich.C@EMPOWERgmat.com posted a reply to A paint crew gets a rush order to paint 80 houses in a new d in the Problem Solving forum
“Hi All, We''re told that a paint crew gets a rush order to paint 80 houses in a new development. They paint the first Y houses at a rate of X houses per week. Realizing that they''ll be late at this rate, they bring in some more painters and paint the rest of the houses at the rate of 1.25X ...”
February 1, 2019
Rich.C@EMPOWERgmat.com posted a reply to Two-thirds of the roads from A to B are at least 5 miles in the Problem Solving forum
“Hi All, We''re told that 2/3 of the roads from A to B are at least 5 miles long, and 1/4 of the roads from B to C are at least 5 miles long. We''re asked to randomly pick a road from A to B and then randomly pick a road from B to C and determine the probability that AT LEAST ONE of the roads you ...”
February 1, 2019
Rich.C@EMPOWERgmat.com posted a reply to Is tutoring necessary for Verbal? in the GMAT Strategy forum
“Hi kyuhunl, The degree to which you might find tutoring useful will depend greatly on the study materials that you''re currently using and how quickly you can learn (and properly practice) certain concepts and Tactics. Before I can offer you the specific advice that you’re looking for, it ...”
February 1, 2019
Brent@GMATPrepNow posted a reply to Perpendicular lines m and n... in the Data Sufficiency forum
“ Given: Perpendicular lines m and n intersect at (0,b) Target question: What is the value of b? Statement 1: The slope of the line m is -1/2 Since line n is PERPENDICULAR to line m, we know that line n has slope 2 However, we can raise and lower the two lines so that the value of b is ...”
February 1, 2019
Max@Math Revolution posted a new topic called If ( x – y – 2 )^2 + ( x + z + 3 )^2 = 0, then what is the v in the Problem Solving forum
“[GMAT math practice question] If ( x – y – 2 )^2 + ( x + z + 3 )^2 = 0, then what is the value of y + z? A. 0 B. 3 C. -3 D. 5 E. -5”
February 1, 2019
Max@Math Revolution posted a reply to {an} is a sequence satisfying an+2 = an+1 + an. If a1 = a4 = in the Problem Solving forum
“=> a3 = a2 + a1 = a2 + 2. a4 = a3 + a2 = a2 + (a2 + 2) = 2a2 + 2 = 2. Thus, a2 = 0 and a3 = 2. Therefore, a5 = a4 + a3 = 2 + 2 = 4, a6 = a5 + a4 = 4 + 2 = 6, and a7 = a6 + a5 = 6 + 4 = 10. Therefore, the answer is A. Answer: A”
February 1, 2019
Max@Math Revolution posted a new topic called If p, x, and y are integers, x^p/x^q=? in the Data Sufficiency forum
“[GMAT math practice question] If p, x, and y are integers, x^p/x^q=? 1) p=q+4 2) x^q=16”
February 1, 2019
Max@Math Revolution posted a reply to Five data values are 11, 14, 16, 18 and x. What is the valu in the Data Sufficiency forum
“=> Forget conventional ways of solving math questions. For DS problems, the VA (Variable Approach) method is the quickest and easiest way to find the answer without actually solving the problem. Remember that equal numbers of variables and independent equations ensure a solution. Since we ...”
February 1, 2019
Rich.C@EMPOWERgmat.com posted a reply to Suppose we have six marbles: 3 blue marbles, 2 red marbles, in the Problem Solving forum
“Hi All, We''re told that we have six marbles: 3 blue marbles, 2 red marbles, and one green marble - and that we are going to put them into three cups: a black cup, a white cup, and a purple cup. The only restriction is that the two red marbles CANNOT be in the same cup, meaning that we could put ...”
January 31, 2019
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 ...”
January 31, 2019
Max@Math Revolution posted a new topic called f(2x-1) = ( x + 2 ) / ( x – 2 ). What is f(x)? in the Problem Solving forum
“[GMAT math practice question] f(2x-1) = ( x + 2 ) / ( x – 2 ). What is f(x)? A. f(x) = ( x + 5 ) / ( x – 3 ) B. f(x) = ( x - 5 ) / ( x + 3 ) C. f(x) = ( x + 5 ) / ( x + 3 ) D. f(x) = ( x – 5 ) / ( x – 3 ) E. f(x) = ( x + 3 ) / ( x – 3 )”
January 31, 2019
Max@Math Revolution posted a reply to f(x) has the properties, f(x+y) = x + f(y) and f(0) = 5. Wha in the Problem Solving forum
“=> Using f(x +y ) = x + f(y) yields f(x) = f(x+0) = x + f(0) Now, using f(0) = 5 yields f(x) = x + 5. Therefore, f(100) = 100 + 5 = 105. Therefore, the answer is C. Answer: C ”
January 31, 2019
Max@Math Revolution posted a new topic called Is 3 a factor of x? in the Data Sufficiency forum
“[GMAT math practice question] Is 3 a factor of x? 1) x-3 is divisible by 6 2) x+3 is divisible by 6”
January 31, 2019
Max@Math Revolution posted a reply to If operation # represents one of addition, subtraction, mult in the Data Sufficiency forum
“=> Forget conventional ways of solving math questions. For DS problems, the VA (Variable Approach) method is the quickest and easiest way to find the answer without actually solving the problem. Remember that equal numbers of variables and independent equations ensure a solution. The ...”
January 31, 2019
Max@Math Revolution posted a new topic called [Math Revolution] Practice “Math Questions of the Day” in the GMAT Math forum
“To help you sharpen your math skills and hit your target score of Q49-51, we are sending you 4 math questions (2 DS, 2 PS) and solutions regularly. These questions are the types of questions appearing in GMAT exam frequently. Please Click the link for solutions. ...”
January 31, 2019
Rich.C@EMPOWERgmat.com posted a reply to A doctor prescribed 18 cubic centimeters of a certain drug t in the Problem Solving forum
“Hi All, This question is essentially about working through the necessary arithmetic. Thankfully, the math itself isn''t that tough, but you do have to stay organized to make sure that you''re setting up the proper calculations. We''re told that a typical dose of a drug is 2 cm^3 per 15 ...”
January 31, 2019
Rich.C@EMPOWERgmat.com posted a reply to A metal company's old machine makes bolts at a constant rate in the Problem Solving forum
“Hi All, The answer choices to this question provide a fantastic shortcut. With the two machines that we''re given, we know that... Old Machine = 100 bolts/hour New Machine = 150 bolts/hour If they start at the same time, the two machines will create 250 bolts/hour The question asks ...”
January 31, 2019
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 ...”
January 31, 2019
Rich.C@EMPOWERgmat.com posted a reply to What is the greatest prime factor of 3^6 - 1? in the Problem Solving forum
“Hi All, A number of the posts have provided elegant solutions to this question. The basic math behind this prompt is Arithmetic and Prime Factorization though, so if you don''t immediately "see" the elegant approach, you can still get to the answer.... We''re asked to find the ...”
January 31, 2019
Brent@GMATPrepNow posted a reply to How many females? (GMAT Prep 2) in the Data Sufficiency forum
“Target question: What percent of the students in the class were females? 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 ...”
January 30, 2019
Brent@GMATPrepNow posted a reply to A doctor prescribed 18 cubic centimeters of a certain drug t in the Problem Solving forum
“We can use equivalent ratios to determine what the dosage SHOULD have been. We''ll use the ratio of drug dosage (in cubic centimeters)/body weight (in pounds) Let x = the dosage (in cubic centimeters) the patient SHOULD have received We get: 2/15 = x/120 Cross multiply to get: 15x = ...”
January 30, 2019
Max@Math Revolution posted a new topic called {an} is a sequence satisfying an+2 = an+1 + an. If a1 = a4 = in the Problem Solving forum
“n} is a sequence satisfying an+2 = an+1 + an. If a1 = a4 = 2, what is the value of a7? A. 10 B. 12 C. 14 D. 15 E. 16”
January 30, 2019
Max@Math Revolution posted a reply to What is the value of (2^8 + 2^9 + 2^{10} + 2^{11}) / 32? in the Problem Solving forum
“=> $$\frac{\left(2^8+2^9+2^{10}+2^{11}\right)}{32}$$ $$=\frac{\left(2^8+2^82^1+2^82^2+2^82^3\right)}{2^5}$$ $$=\frac{2^8\left(1+2^1+2^2+2^3\right)}{2^5}$$ $$=2^3\left(1+2+4+8\right)$$ $$=8\cdot15$$ $$=120$$ Therefore, the answer is D. Answer: D”
January 30, 2019
Max@Math Revolution posted a new topic called Five data values are 11, 14, 16, 18 and x. What is the valu in the Data Sufficiency forum
“[GMAT math practice question] Five data values are 11, 14, 16, 18 and x. What is the value of x? 1) The mode of the 5 data values is 11 2) The average (arithmetic mean) of the 5 data values is 14”
January 30, 2019
Max@Math Revolution posted a reply to If n is positive integer, is 4^n+n^2+1 divisible by 2? in the Data Sufficiency forum
“=> Forget conventional ways of solving math questions. For DS problems, the VA (Variable Approach) method is the quickest and easiest way to find the answer without actually solving the problem. Remember that equal numbers of variables and independent equations ensure a solution. The first ...”
January 30, 2019
Brent@GMATPrepNow posted a reply to Marla starts running around a circular track at the same... in the Problem Solving forum
“Let t = the time (in HOURS) that it takes Marla to complete 4 more laps than Nick. So, after t hours, we can write: (Marla''s lap count) = (Nick''s lap count) + 4 Now that we have a "word equation" we need only fill in the missing information Marla completes 32 laps per hour We can ...”
January 29, 2019
Brent@GMATPrepNow posted a reply to Paul, a painter, paints only flowers or cats in his notebook in the Data Sufficiency forum
“I thought I''d point out that the approach demonstrated by Fabio and Jay is 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 paintings, and the ...”
January 29, 2019
Brent@GMATPrepNow posted a reply to f(x) has the properties, f(x+y) = x + f(y) and f(0) = 5. Wha in the Problem Solving forum
“Given: f(x+y) = x + f(y) What is the value of f(100)? We need to somehow use the fact that f(0) = 5 to help us determine the value of f(100). Notice that we can rewrite 100 as 100 + 0 According to our the function f, we know that: f(100 + 0) = 100 + f(0) = 100 + 5 = 105 Answer: C ...”
January 29, 2019
Brent@GMATPrepNow posted a reply to Leila is playing a carnival game in which she is given 4 in the Problem Solving forum
“Given: P(succeeds on 1 throw) = 1/5 P(succeeds at least 3 times) = P(succeeds 4 times OR succeeds 3 times) = P(succeeds 4 times) + P(succeeds 3 times) P(succeeds 4 times) P(succeeds 4 times) = P(succeeds 1st time AND succeeds 2nd time AND succeeds 3rd time AND succeeds 4th time) = ...”
January 29, 2019
Brent@GMATPrepNow posted a reply to A waitress's income consist of her salary and tips. During in the Problem Solving forum
“APPROACH #1 - start with a convenient value of the server''s salary Let''s say her salary is $4 GIVEN: her tips were 5/4 of her salary 5/4 of $4 = $5 So, her tip total was $5 What fraction of her income for the week came from tips? Income = salary + tips = $4 + $5 = $9 Fraction = $5 /$9 ...”
January 29, 2019
Brent@GMATPrepNow posted a reply to To create a part for a certain piece of machinery, four equa in the Problem Solving forum
“IMPORTANT: the diagrams in GMAT problem solving questions are DRAWN TO SCALE unless stated otherwise. We can use this fact to solve the question by simply "eyeballing" the diagram. The question is basically asking us to determine what percent of the circle is NOT shaded. Well, ...”
January 29, 2019
Brent@GMATPrepNow posted a reply to If (x+y)/z = -2, is x positive? in the Data Sufficiency forum
“Target question: Is x positive? Given: (x + y)/z = -2 Since the question asks about the variable x, let''s solve this equation for x. (x + y)/z = -2 So, x + y = -2z And, x = -2z - y This allows us to REPHRASE the target question.... REPHRASED target question: Is -2z - y positive? ...”
January 29, 2019
Max@Math Revolution posted a new topic called f(x) has the properties, f(x+y) = x + f(y) and f(0) = 5. Wha in the Problem Solving forum
“[GMAT math practice question] f(x) has the properties, f(x+y) = x + f(y) and f(0) = 5. What is the value of f(100)? A. 95 B. 100 C. 105 D. 120 E. 135”
January 29, 2019
Max@Math Revolution posted a new topic called If operation # represents one of addition, subtraction, mult in the Data Sufficiency forum
“[GMAT math practice question] If operation # represents one of addition, subtraction, multiplication, and division, what is the value of 0 # 1? 1) 2 # 1 = 2 2) 4 # 2 = 2”
January 29, 2019
Rich.C@EMPOWERgmat.com posted a reply to A new tower has just been built at the Verbico military in the Problem Solving forum
“Hi j_shreyans, I''m a big fan of TESTing Values (Mitch''s explanation), but this question can also be solved with algebra…. We''re told that adding a new tower to an existing hospital allows fore 3 times the number of available beds that were there before the tower was built: Just the ...”
January 28, 2019
Rich.C@EMPOWERgmat.com posted a reply to A certain company has 18 equally qualified applicants for 4 in the Problem Solving forum
“Hi All, We''re told that a certain company has 18 equally qualified applicants for 4 open positions. We''re asked for the number of different groups of 4 applicants that can be chosen by the company to fill the positions if the order of selection does not matter. This question is a fairly ...”
January 28, 2019
Rich.C@EMPOWERgmat.com posted a reply to When 12 marbles are added to a rectangular aquarium, the wat in the Problem Solving forum
“Hi All, We''re told that when 12 marbles are added to a rectangular aquarium, the water in the aquarium rises 1 1/2 inches. We''re asked how many marbles must be added to the aquarium in total to raise the water 2 3/4 inches. This question is ultimately about ratios, so you can approach the math ...”
January 28, 2019
Brent@GMATPrepNow posted a reply to The table above shows the GPA of 20 students last semester. in the Problem Solving forum
“---------------ASIDE-------------- A little extra background on standard deviations above and below the mean If, for example, a set has a standard deviation of 4, then: 1 standard deviation = 4 2 standard deviations = 8 3 standard deviations = 12 1.5 standard deviations = 6 0.25 ...”
January 28, 2019
Max@Math Revolution posted a new topic called What is the value of (2^8 + 2^9 + 2^{10} + 2^{11}) / 32? in the Problem Solving forum
“[GMAT math practice question] What is the value of (2^8 + 2^9 + 2^{10} + 2^{11}) / 32? A. 80 B. 96 C. 100 D. 120 E. 160”
January 28, 2019
Max@Math Revolution posted a new topic called If n is positive integer, is 4^n+n^2+1 divisible by 2? in the Data Sufficiency forum
“[GMAT math practice question] If n is positive integer, is 4^n+n^2+1 divisible by 2? 1) n is a multiple of 4 2) n is a multiple of 6”
January 28, 2019
Brent@GMATPrepNow posted a reply to A dental licensure exam requires a 75% minimum score in orde in the Data Sufficiency forum
“ Given: A dental licensure exam requires a 75% minimum score in order to pass each section Target question: Did Jennifer pass the 30-question third section? 75% of 30 = 22.5 So, in order to get at least 75% in the 3rd section, Jennifer must correctly answer 23 or more questions in the 3rd ...”
January 28, 2019
Max@Math Revolution posted a reply to If 2 roots of the equation x^2+px+q=0 are -3 and 2, what is in the Problem Solving forum
“=> The equation of this form with roots -3 and 2 is (x+3)(x-2) = 0 or x^2 + x – 6 = 0. Thus, p = 1 and q = -6, and p + q = -5. Therefore, the answer is A. Answer: A”
January 28, 2019
Max@Math Revolution posted a reply to If x+(1/x)=4, what is the value of x^2+(1/x^2)? in the Problem Solving forum
“=> ( x + 1/x )^2 = x^2 + 2x(1/x) + (1/x)^2 = x^2 + (1/x)^2 + 2 = 4^2 = 16. Thus, x^2 + (1/x)^2 = ( x + 1/x )^2 - 2 = 16 - 2 = 14. Therefore, the answer is C. Answer: C”
January 28, 2019
Max@Math Revolution posted a reply to m+n=? in the Data Sufficiency forum
“=> Forget conventional ways of solving math questions. For DS problems, the VA (Variable Approach) method is the quickest and easiest way to find the answer without actually solving the problem. Remember that equal numbers of variables and independent equations ensure a solution. The first ...”
January 28, 2019
Max@Math Revolution posted a reply to If x and y are non-zero numbers and x ≠ ± y, then ( x^2 + in the Data Sufficiency forum
“=> Forget conventional ways of solving math questions. For DS problems, the VA (Variable Approach) method is the quickest and easiest way to find the answer without actually solving the problem. Remember that equal numbers of variables and independent equations ensure a solution. The first ...”
January 28, 2019
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 ...”
January 27, 2019
Rich.C@EMPOWERgmat.com posted a reply to Machines A and B, working together, take t minutes to in the Problem Solving forum
“Hi All, We''re told that Machines A and B, working together, take T minutes to complete a particular work. Machine A, working alone, takes 64 minutes more than T to complete the same work. Machine B, working alone, takes 25 minutes more than T to complete the same work. We''re asked for the ...”
January 27, 2019
Brent@GMATPrepNow posted a reply to Barbara invests $2400 in the National Bank at 5%. How much in the Problem Solving forum
“Barbara invests $2400 in the National Bank at 5%. So, her annual income for this investment = 5% of $2400 = $120 Let x = the additional money Barbara must invest at 8% So, her annual income for this investment = 8% of x = 0.08x So, Barbara''s TOTAL annual income = $120 + 0.08x We want the ...”
January 27, 2019
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”
January 27, 2019
Rich.C@EMPOWERgmat.com posted a reply to When 12 marbles are added to a rectangular aquarium, the in the Problem Solving forum
“Hi All, We''re told that when 12 marbles are added to a rectangular aquarium, the water in the aquarium rises 1 1/2 inches. We''re asked how many marbles must be added to the aquarium in total to raise the water 2 3/4 inches. This question is ultimately about ratios, so you can approach the math ...”
January 26, 2019
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 entire investment. This question can be approached in a number of different ways, including by ...”
January 26, 2019
Brent@GMATPrepNow posted a reply to Probability/ combination in the Problem Solving forum
“P(Tamara and Inga are BOTH chosen for the jury) = (# of ways to choose 7 people that include Tamara and Inga)/(TOTAL # of ways to choose 7 people) # of ways to choose 7 people that include Tamara and Inga Stage 1: place Tamara and Inga on the jury. This can be accomplished in 1 way Stage 2: ...”
January 26, 2019
Brent@GMATPrepNow posted a reply to A sports team played 100 games last season. Did this team in the Data Sufficiency forum
“Target question: Did this team win at least half of the games it played last season? Rephrased target question: Did this team win more than 49 games? Statement 1: The team won 60% of its first 65 games In other words, the team won 39 of its first 65 games Since we don''t know the results ...”
January 26, 2019
Rich.C@EMPOWERgmat.com posted a reply to Ratio in the Problem Solving forum
“Hi All, We''re told that a in the first M games of a team´s season, the ratio of the team´s wins to its losses was 1:2 and in the subsequent N games, the ratio of the team´s wins to losses was 1:3. If M:N = 4:5, we''re asked for the ratio of the team´s wins to its losses for all M+N games. ...”
January 25, 2019
Rich.C@EMPOWERgmat.com posted a reply to A major airplane manufacturer announced the sale of 150 in the Problem Solving forum
“Hi All, We''re told that a major airplane manufacturer announced the sale of 150 small airliners at $125 million each, 75 medium sized airliners at $175 million each, and 60 large airliners at $220 million each. We''re asked for the percentage of the company''s income that came from large and ...”
January 25, 2019
Brent@GMATPrepNow posted a reply to If 2 roots of the equation x^2+px+q=0 are -3 and 2, what is in the Problem Solving forum
“GIVEN: the roots/solutions are x = -3 and x = 2 Notice that x = -3 and x = 2 are solutions to the equation (x + 3)(x - 2) = 0 If we expand and simplify the left side of the equation, we get: x² + x - 6 = 0 So, the equation x² + x - 6 = 0 has roots -3 and 2 Compare this to x² + px + q = 0 to ...”
January 25, 2019
Brent@GMATPrepNow posted a reply to The numbers m, n, and K are all positive integers. Given tha in the Problem Solving forum
“Different approach: The question asks "which of the following must also be a positive integer factor of K?" So, if we can find an answer choice that is NOT a factor of K we can ELIMINATE that answer choice. A. m + n If K = 12, then if COULD be the case that m = 4 and n = 6 In ...”
January 25, 2019
Brent@GMATPrepNow posted a reply to The numbers m, n, and K are all positive integers. Given tha in the Problem Solving forum
“GIVEN: m is a factor of K This means that we can write: K = md for some integer d If m and d are both integers, then m and d are both factors of K Notice that, if K = md, then d = K/m, which means K/m is a factor of K Answer: D Cheers, Brent”
January 25, 2019
Brent@GMATPrepNow posted a reply to If, J, K, L, M, and N are positive integers in ascending ord in the Data Sufficiency forum
“ Given: J, K, L, M, and N are positive integers in ascending order Target question: What is the value of L? Statement 1: The value of K is 3. There are many scenarios that satisfy statement 1. Here are two: Case a: J = 1, K = 3, L = 4, M = 7, N = 8. In this case, the answer to the ...”
January 25, 2019
Max@Math Revolution posted a new topic called If 2 roots of the equation x^2+px+q=0 are -3 and 2, what is in the Problem Solving forum
“[Math Revolution GMAT math practice question] If 2 roots of the equation x^2+px+q=0 are -3 and 2, what is the value of p + q? A. -5 B. -3 C. -1 D. 0 E. 1”
January 25, 2019
Max@Math Revolution posted a reply to What is the measure of each interior angle of a regular deca in the Problem Solving forum
“=> The sum of all interior angles of n-gon is (n-2)*180°. A decagon is a 10-gon. The sum of all interior angles is (10-2)* 180° = 8*180°. And each interior angle of a regular decagon has measure 8*180° / 10 = 8*18° = 144°. Therefore, the answer is E. Answer: E”
January 25, 2019
Max@Math Revolution posted a new topic called m+n=? in the Data Sufficiency forum
“[Math Revolution GMAT math practice question] m+n=? 1) (4^m)(2^n)=16 2) (2^{2m})(4^n)=64”
January 25, 2019
Max@Math Revolution posted a reply to x=? in the Data Sufficiency forum
“=> Forget conventional ways of solving math questions. For DS problems, the VA (Variable Approach) method is the quickest and easiest way to find the answer without actually solving the problem. Remember that equal numbers of variables and independent equations ensure a solution. Since we ...”
January 25, 2019
Brent@GMATPrepNow posted a reply to Mary and Kate are running clockwise around a circular track in the Problem Solving forum
“To get a better idea of what''s happening, let''s sketch the set-up: https://i.imgur.com/SwHzFJD.png Mary is faster than Kate, we can say that Kate has a 250 meter head start. In other words, when Mary closes that 250-meter gap, she will pass Kate for the FIRST time. ...”
January 24, 2019
Rich.C@EMPOWERgmat.com posted a reply to A miniature roulette wheel is divided into 10 equal sectors, in the Problem Solving forum
“Hi All, We''re told that a miniature roulette wheel is divided into 10 equal sectors, each bearing a distinct integer from 1 to 10, inclusive. Each time the wheel is spun, a ball randomly determines the winning sector by settling in that sector and the wheel is spun three times. We''re asked for ...”
January 24, 2019
Rich.C@EMPOWERgmat.com posted a reply to The total cost of a vacation was divided among 3 people. If in the Problem Solving forum
“Hi All, We''re told that the total cost of a vacation was divided equally among 3 people and that if the total cost of the vacation had been divided equally among 4 people, then the cost per person would have been $50 LESS. We''re asked for the total cost of the vacation. This question can be ...”
January 24, 2019
Rich.C@EMPOWERgmat.com posted a reply to A shirt that costs k dollars is increased by 30%, then by an in the Problem Solving forum
“Hi All, We''re told that the price of a shirt that costs K dollars is increased by 30%, then that price is increased by an additional 50%. We''re asked for the final price of the shirt in dollars, in terms of K. This question can be solved in a number of different ways - including Algebraically ...”
January 24, 2019
Brent@GMATPrepNow posted a reply to In the rectangular coordinate system above, the area of tria in the Problem Solving forum
“Let''s draw a rectangle around the triangle (as shown below) and then subtract from the rectangle''s area (28) the areas of the 3 right triangles that surround the triangle in question. We get the following: http://s13.postimage.org/a47qx0j8j/triangle_in_coordinate_plane_2.jpg So, the area ...”
January 24, 2019
Brent@GMATPrepNow posted a reply to A shirt that costs k dollars is increased by 30%, then by an in the Problem Solving forum
“A shirt that costs k dollars is increased by 30%, So, the new coast = k + (30% of k) = k + 0.3k = 1.3k ASIDE So, increasing a value by 30% is the same as multiplying that value by 1.3 Similarly, increasing a value by 20% is the same as multiplying that value by 1.2 And increasing a value by ...”
January 24, 2019
Brent@GMATPrepNow posted a reply to The total cost of a vacation was divided among 3 people. If in the Problem Solving forum
“Let T = total cost of vacation So, T/3 = cost per person with THREE people And T/4 = cost per person with FOUR people If the total cost of the vacation had been divided equally among 4 people, the cost per person would have been $50 less. In other words (cost per person with FOUR people) = ...”
January 24, 2019
Max@Math Revolution posted a new topic called If x+(1/x)=4, what is the value of x^2+(1/x^2)? in the Problem Solving forum
“[Math Revolution GMAT math practice question] If x+(1/x)=4, what is the value of x^2+(1/x^2)? A. 10 B. 12 C. 14 D. 16 E. 18”
January 24, 2019
Max@Math Revolution posted a reply to A = (2-3+4)^{11}, and B = (-2+3-4)^{11}. What is the value o in the Problem Solving forum
“=> A + B = (2-3+4)^{11}+ (-2+3-4)^{11} = 3^{11}+ (-3)^{11} = 3^{11}- 3^{11} = 0. Therefore, 2^{A+B} = 2^0 = 1. Therefore, the answer is C. Answer: C”
January 24, 2019
Max@Math Revolution posted a new topic called If x and y are non-zero numbers and x ≠ ± y, then ( x^2 + y^ in the Data Sufficiency forum
“[Math Revolution GMAT math practice question] If x and y are non-zero numbers and x ≠ ± y, then ( x^2 + y^2 ) / ( x^2 - y^2 )=? 1) |x/y| = 1/3 2) y = -3x”
January 24, 2019
Max@Math Revolution posted a reply to If y=|x-1|+|x+1|, then y=? in the Data Sufficiency forum
“=> Forget conventional ways of solving math questions. For DS problems, the VA (Variable Approach) method is the quickest and easiest way to find the answer without actually solving the problem. Remember that equal numbers of variables and independent equations ensure a solution. The first ...”
January 24, 2019
Rich.C@EMPOWERgmat.com posted a reply to Getting out of a Rut: Overcoming 680 over 3 consecutive atte in the I just Beat The GMAT! forum
“Hi markymarc89, That''s OUTSTANDING news! With a 740/Q50, you can comfortably apply to ANY Business Schools that interest you. Since you''ve already taken care of your applications, there''s not much else to do at this point (unless you want to consider applying to any additional Schools). We''re ...”
January 23, 2019
Brent@GMATPrepNow posted a reply to A restaurant meal cost $35.50 and there was no tax. If the t in the Problem Solving forum
“Let''s first see what happens when the tip is 10% 10% of $35.50 = $3.55 So, the total cost (WITH a 10% tip) = $35.50 + $3.55 = $39.05 So, the total cost must be GREATER THAN $39.05 This means the TOTAL cost could be $39.06 Check the answer choices.... A, D and E do not allow for the total cost ...”
January 23, 2019
Brent@GMATPrepNow posted a reply to If i, a and b are integers, is 4(3b + 2) = 5a? (1) If i is in the Data Sufficiency forum
“Target question: Is 4(3b + 2) = 5a? Statement 1: If i is divided by 5 the quotient is a and the remainder is 3 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 ...”
January 23, 2019
Brent@GMATPrepNow posted a reply to If the average of four numbers is 35, how many of the number in the Data Sufficiency forum
“ Given: The average of four numbers is 35 Target question: How many of the numbers are less than 35? If we''re able to see that the statements FEEL insufficient, and we''re able to come up with some counter-examples in our head, then we can head straight to... . . . Statements 1 and 2 ...”
January 23, 2019
Brent@GMATPrepNow posted a reply to If x is a positive integer, is x<16? 1) x is less than t in the Data Sufficiency forum
“Target question: Is x < 16? Statement 1: x is less than the average (arithmetic mean) of the first ten positive integers Since the first ten positive integers are EQUALLY SPACED, the average = (smallest number + biggest number)/2 = (1 + 10)/2 = 5.5 So, x < 5.5 Since 5.5 < 16, we ...”
January 23, 2019
Brent@GMATPrepNow posted a reply to What is the measure of each interior angle of a regular deca in the Problem Solving forum
“Useful rule: the sum of the angles in an n-sided polygon = (n - 2)(180º) So, for example, the sum of the angles in an 11-sided polygon = (11 - 2)(180º) = (9)(180º) = 1620º What is the measure of each interior angle of a regular decagon? A decagon has 10 sides. The sum of the angles in ...”
January 23, 2019
Brent@GMATPrepNow posted a reply to x=? in the Data Sufficiency forum
“Target question: What is the value of x? Statement 1: x³ - x = 0 Factor to get: x(x² - 1) = 0 Factor again to get: x(x + 1)(x - 1) = 0 So, it could be the case that x = 0, x = -1 or x = 1 Since we cannot answer the target question with certainty, statement 1 is NOT SUFFICIENT ...”
January 23, 2019
Brent@GMATPrepNow posted a reply to Ayayai electronics is a company manufacturing MP3 players. in the Problem Solving forum
“I thought I''d point out that Jay''s approach is 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 MP3 players, and the two characteristics are: ...”
January 23, 2019
Max@Math Revolution posted a new topic called What is the measure of each interior angle of a regular deca in the Problem Solving forum
“[Math Revolution GMAT math practice question] What is the measure of each interior angle of a regular decagon? A. 72° B. 108° C. 120° D. 135° E. 144°”
January 23, 2019
Max@Math Revolution posted a reply to If x-2y=4, then x^2-4xy+4y^2-x+2y=? in the Problem Solving forum
“=> x^2-4xy+4y^2-x+2y =(x-2y)^2 – (x-2y) =4^2 – 4 = 16 – 4 = 12. Therefore, the answer is A. Answer: A”
January 23, 2019
Max@Math Revolution posted a new topic called x=? in the Data Sufficiency forum
“[Math Revolution GMAT math practice question] x=? 1) x^3-x=0 2) x=-x”
January 23, 2019
Max@Math Revolution posted a reply to n is a 3 digit integer of the form ab6. Is n divisible by 4? in the Data Sufficiency forum
“=> Forget conventional ways of solving math questions. For DS problems, the VA (Variable Approach) method is the quickest and easiest way to find the answer without actually solving the problem. Remember that equal numbers of variables and independent equations ensure a solution. The first ...”
January 23, 2019
Max@Math Revolution posted a new topic called [Math Revolution] Practice “Math Questions of the Day” in the GMAT Math forum
“To help you sharpen your math skills and hit your target score of Q49-51, we are sending you 4 math questions (2 DS, 2 PS) and solutions regularly. These questions are the types of questions appearing in GMAT exam frequently. Please Click the link for solutions. ...”
January 23, 2019
Brent@GMATPrepNow posted a reply to If when a certain integer x is divided by 5, the remainder in the Problem Solving forum
“Here''s another (longer) approach: 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 ...”
January 22, 2019
Brent@GMATPrepNow posted a reply to If Polygon X has fewer than 9 sides, how many sides does in the Data Sufficiency forum
“Target question: How many sides does Polygon X have? Given: Polygon X has fewer than 9 sides Useful rule: The sum of the angles in an n-sided polygon = (n - 2)(180º) Since the polygon has FEWER than 9 sides, there are are exactly SIX possible cases: case a: There are 8 sides, in ...”
January 22, 2019
Rich.C@EMPOWERgmat.com posted a reply to Of the votes cast on a certain proposal, 80 more were in in the Problem Solving forum
“Hi All, We''re told that of the votes cast on a certain proposal, 80 MORE were in favor of the proposal than were against it and the number of votes against the proposal was 40 percent of the TOTAL vote. We''re asked for the total number of votes cast? (Each vote cast was either in favor of the ...”
January 22, 2019
Rich.C@EMPOWERgmat.com posted a reply to Which of the following is closest to the value of (2^23) in the Problem Solving forum
“Hi All, We''re asked which of the following is closest to the value of (2^23)(5^26). If you don''t immediately see the ''Exponent'' rules that apply to this question, then you can still solve it with some basic Arithmetic and logic. To start, when you multiply a bunch of numbers together, the ...”
January 22, 2019
Rich.C@EMPOWERgmat.com posted a reply to The number 75 can be written as the sum of the squares of 3 in the Problem Solving forum
“Hi All, This question can be solved with a bit of ''brute force'' arithmetic, but the speed with which you solve it will likely depend on how quickly you can write everything down and how you do the work. We''re asked to find the three positive integers, whose squares add up to 75. To start, ...”
January 22, 2019
Brent@GMATPrepNow posted a reply to The number 75 can be written as the sum of the squares of 3 in the Problem Solving forum
“We''re looking for 3 DIFFERENT squares that add to 75 Here are the only squares we need to consider: 1, 4, 9, 16, 25, 36, 49, 64 Can you find 3 that add to 75? After some fiddling, we may notice that 1 + 25 + 49 In other words, 1² + 5² + 7² = 75 We want the SUM of 1 + 5 + 7, which is ...”
January 22, 2019
Brent@GMATPrepNow posted a reply to Bite-sized video lessons from GMAT Prep Now in the GMAT Math forum
“Data Sufficiency Video #2: The Elimination Method Video: https://www.youtube.com/watch?v=amhxP9My_pU Cheers, Brent”
January 22, 2019
Max@Math Revolution posted a new topic called A = (2-3+4)^{11}, and B = (-2+3-4)^{11}. What is the value o in the Problem Solving forum
“[Math Revolution GMAT math practice question] A = (2-3+4)^{11}, and B = (-2+3-4)^{11}. What is the value of 2^{A+B}? A. 1/2048 B. 1/1024 C. 1 D. 1024 E. 2048”
January 22, 2019
Max@Math Revolution posted a new topic called If y=|x-1|+|x+1|, then y=? in the Data Sufficiency forum
“[Math Revolution GMAT math practice question] If y=|x-1|+|x+1|, then y=? 1) x > -1 2) x < 1”
January 22, 2019
Brent@GMATPrepNow posted a reply to The average salary of 15 people in the shipping department in the Problem Solving forum
“]The average salary of 15 people in the shipping department at a certain firm is $20,000 So, (sum of all 15 salaries)/15 = $20,000 Multiply both sides by 15 to get: sum of all 15 salaries = $300,000 The salary of 5 of the employees is $25,000 each and the salary of 4 of the employees is $16,000 ...”
January 21, 2019
ceilidh.erickson posted a reply to In the figure above, segments PQ and QR are each parallel to in the Data Sufficiency forum
“It is generally true in Data Sufficiency that if the question asks you for a PROPORTION, you do not need concrete values to answer it. In this case, we''re asked for a RATIO of horizontal and vertical lengths, but not for actual values. We can think of any slope as a RATIO of vertical to ...”
January 21, 2019
ceilidh.erickson posted a reply to At a certain fruit stand, the price of each apple is 40 cent in the Problem Solving forum
“We can also think of this as a WEIGHTED AVERAGE question. If we buy some 40 cent apples and 60 cent oranges, the average price for all fruit will be between 40 and 60. If we buy more apples, it''ll be closer to 40. If more oranges, it''ll be closer to 60. --|--------------|----| ...”
January 21, 2019
ceilidh.erickson posted a reply to Journalist: Every election year at this time the state gover in the Critical Reasoning forum
“For more on using this strategy for BOLDFACE questions on CR, see: https://www.beatthegmat.com/most-of-western-music-since-the-renaissance-has-been-based-t305309.html#823603 https://www.beatthegmat.com/gmat-official-guide-2019-in-countries-where-automobile-t303686.html#818265 ...”
January 21, 2019
ceilidh.erickson posted a reply to What is the average (arithmetic mean) of x, y, and z? in the GMAT Math forum
“You should always start by REPHRASING any DS question to determine: what''s the minimum information that would be sufficient to answer this question? Our question is "what is the average of x, y, and z?" First, rephrase algebraically: (x + y + z)/3 = ? What would we need in order ...”
January 21, 2019
ceilidh.erickson posted a reply to Journalist: Every election year at this time the state gover in the Critical Reasoning forum
“The goal in any BOLDFACE question is to deconstruct the argument, and determine the role of each statement: - author''s conclusion / position - reasoning that supports the author''s position - the counterpoint / what others believe - support for the counterpoint - neutral / background ...”
January 21, 2019
ceilidh.erickson posted a reply to As even most smokers will admit, smoking is both unhealthy a in the Sentence Correction forum
“This two-part parallelism - also known as CLOSED PARALLELISM - is very common on the GMAT. Any time you see the following: BOTH ____ AND ____ EITHER ____ OR ______ NOT ONLY _____BUT ALSO _______ NOT ________ BUT _________ etc, ... you need to make sure that what comes right after the ...”
January 21, 2019
ceilidh.erickson posted a reply to As even most smokers will admit, smoking is both unhealthy a in the Sentence Correction forum
“This question is testing PARALLELISM and SUBJECT/VERB agreement. When there is a closed parallel marker such as BOTH X AND Y, the part of the sentence that follows "both" must be parallel to the part that follows "and." In each of the answer choices, I''ve highlighted what ...”
January 21, 2019
Brent@GMATPrepNow posted a reply to A triangle has side lengths of a, b, and c centimeters. in the GMAT Math forum
“Target question: Does each angle in the triangle measure less than 90 degrees? Given: A triangle has side lengths of a, b, and c centimeters Statement 1: The 3 semicircles whose diameters are the sides of the triangle have areas that are equal to 3 cm², 4 cm², and 6 cm², respectively. ...”
January 21, 2019
ceilidh.erickson posted a reply to The senate candidate expressed outrage that few judges have in the Critical Reasoning forum
“This is NOT a Manhattan Prep question. It is not even a GMAT-style question; it is an LSAT-style question. Students should disregard this question. The poster should also take care to only cite sources if he/she got the problem directly from the source. This problem seems to have been taken from ...”
January 21, 2019
Brent@GMATPrepNow posted a reply to If x-2y=4, then x^2-4xy+4y^2-x+2y=? in the Problem Solving forum
“GIVEN: x - 2y = 4 We want to find the value of x² - 4xy + 4y² - x + 2y We should notice that x² - 4xy + 4y² is equal to (x - 2y)² We should notice that - x + 2y is equal to -(x - 2y) We get: x² - 4xy + 4y² - x + 2y = (x - 2y)² - (x - 2y) Now replace x - 2y with 4 to get: = (x - ...”
January 21, 2019
Brent@GMATPrepNow posted a reply to What is the value of z in the triangle above? (1) x+y=139 ( in the Data Sufficiency forum
“Target question: What is the value of z in the triangle above? IMPORTANT: Since angles in a triangle must add to 180 degrees, we can write: x + y + z = 180 Statement 1: x + y = 139 Take: x + y + z = 180 and replace (x + y) with 139 to get: 139 + z = 180 Solve equation for z to get: z = 41 ...”
January 21, 2019
Brent@GMATPrepNow posted a reply to 10 different biology books and 8 different chemistry books l in the Problem Solving forum
“Take the task of selecting 4 books and break it into stages. Stage 1: Select two biology books Since the order in which we select the books does not matter, we can use combinations. We can select 2 books from 10 books in 10C2 ways (45 ways) So, we can complete stage 1 in 45 ways If ...”
January 21, 2019
Brent@GMATPrepNow posted a reply to What was the number of defective batteries in a shipment of in the Data Sufficiency forum
“Target question: What was the number of defective batteries in a shipment of 4000 batteries? Statement 1: In a particular sample of 10 batteries selected from the shipment, 1 was defective. Don''t make the mistake of assuming that this means 1/10 of ALL batteries are defective. There''s no ...”
January 21, 2019
Max@Math Revolution posted a new topic called If x-2y=4, then x^2-4xy+4y^2-x+2y=? in the Problem Solving forum
“[Math Revolution GMAT math practice question] If x-2y=4, then x^2-4xy+4y^2-x+2y=? A. 12 B. 16 C. 20 D. 24 E. 28”
January 21, 2019
Max@Math Revolution posted a new topic called n is a 3 digit integer of the form ab6. Is n divisible by 4? in the Data Sufficiency forum
“[Math Revolution GMAT math practice question] n is a 3 digit integer of the form ab6. Is n divisible by 4? 1) a+b is an even integer 2) ab is an odd integer.”
January 21, 2019
Max@Math Revolution posted a reply to 32 teams compete in the World Cup of Soccer. They are divid in the Problem Solving forum
“=> Each group plays 4C2 = 6 games and we have 8 groups. Thus, the group stage includes 6*8 = 48 games. Therefore, the answer is C. Answer: C”
January 21, 2019
Max@Math Revolution posted a reply to The speed of a boat is 5 times the speed at which a river fl in the Problem Solving forum
“=> Let d and v be the distance the boat travels and the speed of the river flow, respectively. The time the boat takes to travel up the river is d / ( 5v – v ) = d/4v. The time the boat takes to travel down the river is d / ( 5v + v ) = d/6v. Let p be the percentage are looking for. ...”
January 21, 2019
Max@Math Revolution posted a reply to Is ab < 0? in the Data Sufficiency forum
“=> Forget conventional ways of solving math questions. For DS problems, the VA (Variable Approach) method is the quickest and easiest way to find the answer without actually solving the problem. Remember that equal numbers of variables and independent equations ensure a solution. The first ...”
January 21, 2019
Max@Math Revolution posted a reply to A sequence An satisfies An+3=An+8. What is the remainder whe in the Data Sufficiency forum
“=> Forget conventional ways of solving math questions. For DS problems, the VA (Variable Approach) method is the quickest and easiest way to find the answer without actually solving the problem. Remember that equal numbers of variables and independent equations ensure a solution. The first ...”
January 21, 2019
Rich.C@EMPOWERgmat.com posted a reply to If Sam were twice as old as he is, he would be 40 years in the Problem Solving forum
“Hi All, We''re told that if Sam were TWICE as old as he is, then he would be 40 years older than Jim and that Jim is currently 10 years YOUNGER than Sam. We''re asked for Sam''s current age. This question can be solved in a couple of different ways, including by TESTing THE ANSWERS. Since the ...”
January 20, 2019
Rich.C@EMPOWERgmat.com posted a reply to [x] denotes the least integer greater than or equal to x ... in the Problem Solving forum
“Hi All, This is an example of a ''Symbolism'' question - the prompt ''makes up'' a math symbol, tells you what it means, then asks you to perform a calculation using it. When dealing with these types of symbols, it often helps to jot down a few examples, so that you understand the work that will ...”
January 20, 2019
Rich.C@EMPOWERgmat.com posted a reply to On a game show, a contestant is given three keys, each of in the Problem Solving forum
“Hi All, We''re told that on a game show, a contestant is given three keys, each which opens exactly one of three identical boxes. The first box contains $1, the second $100, and the third $1000. The contestant assigns each key to one of the boxes and wins the amount of money contained in any box ...”
January 20, 2019
Brent@GMATPrepNow posted a reply to On a game show, a contestant is given three keys, each of in the Problem Solving forum
“There aren''t many possible outcomes, so let''s start by listing all possibilities. Let A, B and C represent the 3 boxes, and let a, b, c, be the keys for those boxes (in that same order). A = $1 prize, B = $100 prize and C = $1000 prize If the boxes are arranged as A-B-C, then these are ...”
January 20, 2019
Brent@GMATPrepNow posted a reply to Which of the following lists a number of points at which a in the Problem Solving forum
“http://s27.postimg.cc/531tmnqpr/circ_int.jpg Answer: E The important takeaway here is that "intersect" does not necessarily mean "pass through" So, a line that is tangent to a circle (touching the circle but not passing through it) can be said to intersect the circle. To ...”
January 20, 2019
Brent@GMATPrepNow posted a reply to [x] denotes the least integer greater than or equal to x ... in the Problem Solving forum
“First, let''s take a moment to get a good idea of what this strange notation means. A few examples: -1 < x/2 ≤ 0 Multiply all sides of the inequality by 2 to get: -2 < x ≤ 0 Check the answer choices.... Only -3/2 falls inside that range. Answer: B Cheers, Brent”
January 20, 2019
Brent@GMATPrepNow posted a reply to Full Plan in the The 60-Day GMAT Study Guide forum
“Hi Aliya, I have a feeling that your email system is treating the emails as spam. Have you checked your spam/junk folders? You might to sign up for the emails again, but this time, be sure to add guide@beatthegmat.com as a contact in your e-mail system. This will help ensure that the daily ...”
January 20, 2019
Brent@GMATPrepNow posted a reply to The average American spends y dollars on food per month, exc in the Problem Solving forum
“This is a Variables in the Answer Choices question (VIAC). This question type can be answered algebraically or using the INPUT-OUTPUT approach. Mitch has demonstrated the INPUT-OUTPUT approach, so let''s solve the question algebraically. The average American spends y dollars on food per month, ...”
January 20, 2019
Brent@GMATPrepNow posted a reply to If a is a positive integer and 81 divided by a in the Data Sufficiency forum
“Target question: What is the value of a? Given: 81 divided by a results in a remainder of 1 In other words, 81 is 1 greater than some multiple of a This means that 80 is some multiple of a Another way to say this is: a is a divisor of 80 The divisors of 80 are: 1, 2, 4, 5, 8, 10, 16, ...”
January 19, 2019
Brent@GMATPrepNow posted a reply to Set A = {2, 3, 4, 5}, and set B = {4, 5, 6, 7, 8}. If P = th in the Problem Solving forum
“Let''s list and count all possible outcomes. Possible products when 2 is selected from set A: 8, 10, 12, 14, 16 Possible products when 3 is selected from set A: 12, 15, 18, 21, 24 Possible products when 4 is selected from set A: 16, 20, 24, 28, 32 Possible products when 5 is selected from set ...”
January 19, 2019
Brent@GMATPrepNow posted a reply to If Sam were twice as old as he is, he would be 40 years in the Problem Solving forum
“Jim is 10 years younger than Sam Let x = Sam''s PRESENT age So, x - 10 = Jim''s PRESENT age If Sam were twice as old as he is, he would be 40 years older than Jim. TWICE Sam''s age = 2x So, we can write: 2x = (x - 10) + 40 Simplify: 2x = x + 30 Solve: x = 30 Answer: B Cheers, Brent”
January 19, 2019
Brent@GMATPrepNow posted a reply to One night a certain hotel rented 3/4 of its rooms, including in the Problem Solving forum
“This question is a great candidate for the Double Matrix method, whichcan be used for most questions featuring a population in which each member has two characteristics associated with it. Here, we have a population of motel rooms, and the two characteristics are: - air conditioning or no air ...”
January 19, 2019
Brent@GMATPrepNow posted a reply to In a certain pet shop, 1/3 of the pets are dogs and 1/5 of in the Data Sufficiency forum
“Target question: How many of the pets are dogs? Given: 1/3 of pets are dogs & 1/5 of pets are birds Let T = TOTAL number of pets. So, T/3 = number of dogs And T/5 = number of birds Statement 1: There are 30 birds at the pet shop So, T/5 = 30 This means that T = 150, which ...”
January 19, 2019