Brent@GMATPrepNow posted a new topic called Set A = {22, 27, 11, 12, 2}, and set B: {14, 19, 3, 4, x} in the Problem Solving forum
“Set A = {22, 27, 11, 12, 2}, and set B: {14, 19, 3, 4, x} If x < 0, and the standard deviation of set A = the standard deviation of set B, what is the value of x? A) -2 B) -3 C) -4 D) -5 E) -6 Difficulty level: 600-650 Answer: E Source: www.gmatprepnow.com”
Today
Brent@GMATPrepNow posted a reply to x, y and p are integers, and xyp ≠ 0. in the Problem Solving forum
“Two important rules: ODD exponents preserve the sign of the base. So, (NEGATIVE)^(ODD integer) = NEGATIVE and (POSITIVE)^(ODD integer) = POSITIVE An EVEN exponent always yields a positive result (unless the base = 0) So, (NEGATIVE)^(EVEN integer) = POSITIVE and (POSITIVE)^(EVEN integer) ...”
Today
Max@Math Revolution posted a new topic called 21, 22, 23, … , and (20+n) are n consecutive integers. One i in the Problem Solving forum
“[GMAT math practice question] 21, 22, 23, … , and (20+n) are n consecutive integers. One integer is excluded, and the average (arithmetic mean) of the remaining integers is calculated. The minimum possible value of this average is 60. What is the maximum possible value of this average? A. ...”
Today
Max@Math Revolution posted a new topic called What is a? in the Data Sufficiency forum
“[GMAT math practice question] What is a? 1) 3x-[7x-{2x-(5-6x)}] = -10x+4 2) –a+5 = 11x”
Today
Brent@GMATPrepNow posted a new topic called x, y and p are integers, and xyp ≠ 0. in the Problem Solving forum
“x, y and p are integers, and xyp ≠ 0. If p^x < p^y, which of the following MUST be true? i) x − y < 0 ii) x < 2y iii) x^p < y^p A) i only B) ii only C) iii only D) i and ii only E) none of the above Difficulty level: 650-700 Answer: E Source: ...”
Yesterday
Brent@GMATPrepNow posted a reply to Five friends play blackjack in Las Vegas and lose an average in the Problem Solving forum
“Let A, B, C, D and E represent the LOSSES (in dollars) of the 5 friends Five friends play blackjack in Las Vegas and lose an average of $100 each. So, we can write: (A+B+C+D+E)/5 = 100 Multiply both sides by 5 to get: A+B+C+D+E = 500 If the losses of two of the friends total$380, what is ...”
Yesterday
Max@Math Revolution posted a new topic called Tom painted 1/3 of a wall red, 1/5 of the wall blue and the in the Problem Solving forum
“[GMAT math practice question] Tom painted 1/3 of a wall red, 1/5 of the wall blue and the remaining 238 m^2 black. What is the area of the wall in m^2? A. 490 B. 500 C. 510 D. 520 E. 530”
Yesterday
Max@Math Revolution posted a new topic called What is d? in the Data Sufficiency forum
“https://i.postimg.cc/RWxVZpJb/7-15.png 1) b = √3 2) c = 2”
Yesterday
Max@Math Revolution posted a reply to In the diagram, each of a, b, c, … ,g represents one of th in the Problem Solving forum
“=> The number of elements in set A is a + b + c + d. The number in set B is b + c + e + f, and the number of elements in set C is c + d + f + g. The sum of the sizes of these three sets is then a + 2b + 3c + 2d + e + 2f + g. To minimise this total, c must have the smallest value as ...”
Yesterday
Max@Math Revolution posted a reply to As the figure shows, A = -5 and B = 4. If AC:CD:DB=1:2:3, wh in the Problem Solving forum
“=> Since AC:CD:DB = 1:2:3, we can put AC = k, CD = 2k and DB = 3k. Then k + 2k + 3k = 6k = 4 – (-5) = 9 and k = 3/2. Thus, C = A + k = -5 + (3/2) = -(7/2) = -3.5 and D = B – 3k = 4 – 9/2 = -(1/2) = -0.5. Therefore, B is the answer. Answer: B”
Yesterday
Max@Math Revolution posted a reply to A class consists of 30 students. Among them a students have 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 ...”
Yesterday
Max@Math Revolution posted a reply to A river flows at a constant speed of 2 miles per hour. It ta 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 ...”
Yesterday
Brent@GMATPrepNow posted a reply to If k is an integer and 2 < k < 7, for how many differe in the Problem Solving forum
“IMPORTANT RULE: If two sides of a triangle have lengths A and B, then . . . DIFFERENCE between A and B < length of third side < SUM of A and B We''re told that the two KNOWN sides have lengths 2 and 7 So, we can write: (7 - 2) < k < (7 + 2) Simplify: 5 < k < 9 Since k is an ...”
July 14, 2019
Brent@GMATPrepNow posted a reply to For the 5 days shown in the graph, how many kilowatt-hours in the Problem Solving forum
“Where''s the graph? Cheers, Brent”
July 13, 2019
Brent@GMATPrepNow posted a reply to If x and y are both integers greater than 1, is x a multiple in the Data Sufficiency forum
“Target question: Is x a multiple of y? Asking whether x is a multiple of y is the same as asking whether x = (y)(some integer) For example, 12 is a multiple of 3 because 12 = (3)(4) So, let''s rephrase the question as... REPHRASED target question: Does x = (y)(some integer)? Statement 1: ...”
July 12, 2019
Brent@GMATPrepNow posted a reply to In how many different ways can 3 identical green shirts and in the Problem Solving forum
“We can take this question and ask an easier question: In how many ways can we choose 3 of the 6 children to receive a green shirt? Notice that, once we have given a green shirt to each of those 3 chosen children, the remaining children must get red shirts. In other words, once we have given ...”
July 12, 2019
Brent@GMATPrepNow posted a reply to Bill took 4 math tests, and each test received a score out in the Data Sufficiency forum
“Target question: What was Bill''s average (arithmetic mean) score for all 4 tests? Statement 1: Bill''s first 3 tests received an average score of 50. Since we don''t have any information about the 4th test, statement 1 is NOT SUFFICIENT Statement 2: Bill''s last 2 tests received an ...”
July 12, 2019
Brent@GMATPrepNow posted a reply to Did Insurance Company $$K$$ have more than $300 million in in the Data Sufficiency forum “Target question: Did Insurance Company $$K$$ have more than$300 million in total net profits last year? Jump straight to... . . . Statements 1 and 2 combined Statement 2 tells us about profits from ONE PART of Company K''s business. Statement 1 tells us a tiny bit about Company K''s ...”
July 12, 2019
Max@Math Revolution posted a new topic called In the diagram, each of a, b, c, … ,g represents one of the in the Problem Solving forum
“https://i.postimg.cc/4Kn7XMNz/712.png”
July 12, 2019
Max@Math Revolution posted a reply to a, b, c, d satisfy a-1=b+2=c-3=d+4. Which of a, b, c, d is t in the Problem Solving forum
“=> Since a – 1 = b + 2, we have a – b = 3 > 0 or a > b. Since b + 2 = c – 3, we have b = c – 5 or a – b = a – ( c – 5 ) = a – c + 5 = 3 or a – c = -2 < 0. Thus we have c > a > b. Since c – 3 = d + 4, we have c – d = 7 and c > d. Thus c is the largest ...”
July 12, 2019
Max@Math Revolution posted a new topic called A class consists of 30 students. Among them a students have in the Data Sufficiency forum
“[GMAT math practice question] A class consists of 30 students. Among them a students have 90 books, b students have 80 books, c students have 70 books and all the remaining students have 60 books. What is the average number of books the students in the class have? 1) a= b+c 2) a is twice b”
July 12, 2019
Max@Math Revolution posted a reply to Five consecutive integers satisfies a < b < c < d & 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. ...”
July 12, 2019
Max@Math Revolution posted a new topic called a, b, c abd d satisfy a - 1 =b + 2 = c - 3 = d + 4. Which of in the Problem Solving forum
“https://i.postimg.cc/9w5w0K3k/7-12.png”
July 11, 2019
Max@Math Revolution posted a reply to What is 1/2 + 1/6 + 1/12 + 1/20 + 1/30 + 1/42 + 1/56? in the Problem Solving forum
“=> 1/2 + 1/6 + 1/12 + 1/20 + 1/30 + 1/42 + 1/56 = 1/(1*2) + 1/(2*3) + 1/(3*4) + 1/(4*5) + 1/(5*6) + 1/(6*7) + 1/(7*8) = (1/1 – 1/2) + (1/2 – 1/3) + (1/3 – 1/4) + (1/4 – 1/5) + (1/5 – 1/6) + (1/6 – 1/7) + (1/7 – 1/8) = 1/1 – 1/8 = 7/8 Therefore, C is the answer. Answer: C”
July 11, 2019
Max@Math Revolution posted a new topic called A river flows at a constant speed of 2 miles per hour. It ta in the Data Sufficiency forum
“[GMAT math practice question] A river flows at a constant speed of 2 miles per hour. It takes 3 hours for a ship to go a miles upstream. How many hours does it take for the ship to go b miles downstream? 1) a = 6 miles 2) b is longer than a by 3 miles”
July 11, 2019
Max@Math Revolution posted a reply to x, y, z are 3 consecutive positive integers. What is the val 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. ...”
July 11, 2019
Brent@GMATPrepNow posted a reply to a, b, c, d satisfy a-1=b+2=c-3=d+4. Which of a, b, c, d is t in the Problem Solving forum
“Rewrite each value in terms of the same variable. Given: a - 1 = b + 3 Subtract 3 from both sides to get: b = a - 4 Given: a - 1 = c - 3 Add 3 to both sides to get: c = a + 2 Given: a - 1 = d + 4 Subtract 4 from both sides to get: d = a - 5 So, a, b, c and d are equal to a, a-4, a+2 ...”
July 10, 2019
Max@Math Revolution posted a new topic called a, b, c, d satisfy a-1=b+2=c-3=d+4. Which of a, b, c, d is t in the Problem Solving forum
“[GMAT math practice question] a, b, c, d satisfy a-1=b+2=c-3=d+4. Which of a, b, c, d is the largest? A. a B. b C. c D. d E. all same”
July 10, 2019
Max@Math Revolution posted a reply to Let f(n) be the number of positive factors of n. What is min in the Problem Solving forum
“=> Since 420 = 2^2*3*5*7, we have f(420) = (2+1)(1+1)(1+1)(1+1) = 24 and f(x) = 96 / f(420) = 96 / 24 = 4. The smallest integer with 4 factors is 6, which has 4 factors, 1, 2, 3 and 6. Therefore, B is the answer. Answer: B”
July 10, 2019
Max@Math Revolution posted a new topic called Five consecutive integers satisfies a < b < c < d < e. what in the Data Sufficiency forum
“[GMAT math practice question] Five consecutive integers satisfies a < b < c < d < e. what is the maximum of a + e? 1) the summation of five integers is negative 2) e is positive”
July 10, 2019
Max@Math Revolution posted a reply to x, y are two different positive integers greater than 6. Wha 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 ...”
July 10, 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. ...”
July 10, 2019
Brent@GMATPrepNow posted a reply to Bite-sized video lessons from GMAT Prep Now in the GMAT Math forum
“Data Sufficiency lesson #8: - Choosing Good Numbers Video: https://www.youtube.com/watch?v=bu-WhqM0j1Q Cheers, Brent”
July 9, 2019
Max@Math Revolution posted a new topic called What is 1/2 + 1/6 + 1/12 + 1/20 + 1/30 + 1/42 + 1/56? in the Problem Solving forum
“[GMAT math practice question] What is 1/2 + 1/6 + 1/12 + 1/20 + 1/30 + 1/42 + 1/56? A. 3/5 B. 5/8 C. 7/8 D. 8/9 E. 9/10”
July 9, 2019
Max@Math Revolution posted a new topic called x, y, z are 3 consecutive positive integers. What is the val in the Data Sufficiency forum
“[GMAT math practice question] x, y, z are 3 consecutive positive integers. What is the value of x? 1) x < y < z 2) 12+13+14+15 = x+y+z”
July 9, 2019
Brent@GMATPrepNow posted a reply to A certain candy manufacturer reduced the weight of Candy Bar in the Problem Solving forum
“Let''s assign nice values to the ORIGINAL weight and price of the candy bar. Let''s say it ORIGINALLY weight 100 ounces and cost $100$1 per ounce If we decrease the weight be 20%, the NEW weight is 80 ounces. The price remains at $100 per bar So, the NEW price per ounce =$100/80 ounces = ...”
July 8, 2019
Brent@GMATPrepNow posted a reply to While driving on the expressway, did Robin ever exceed the in the Data Sufficiency forum
“NOTE: There''s nothing here to suggest that Robin''s speed was constant. Sure, she MIGHT have traveled at a constant speed, or her speed may have varied throughout the trip. Target question: Did Robin''s speed ever exceed 55 miles per hour? Statement 1: Robin drove 100 miles No information ...”
July 8, 2019
Brent@GMATPrepNow posted a reply to What is the remainder when positive integer x is divided by in the Data Sufficiency forum
“Target question: What is the remainder when positive integer x is divided by 5? Statement 1: x divided by 10 has a remainder of 7. 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 ...”
July 8, 2019
Brent@GMATPrepNow posted a reply to If x and y are greater than 0, is x = 1 ? in the Data Sufficiency forum
“Target question: Is x = 1 ? Given: x and y are POSITIVE Statement 1: x/y = 1 Let''s TEST some values. There are several values of x and y that satisfy statement 1. Here are two: Case a: x = 1 and y = 1. In this case, the answer to the target question is YES, x DOES equal 1 Case b: ...”
July 8, 2019
Brent@GMATPrepNow posted a reply to The function f(a) is defined for all positive integers a as in the Problem Solving forum
“Since 77 = (11)(7), any positive multiple of 7 or 11 will have a common factor with 77 where that common factor is greater than 1. For example, 77 and 14 share a common factor of 7. And 77 and 35 share a common factor of 7. Likewise, 77 and 55 share a common factor of 11. And 77 and 33 share ...”
July 8, 2019
Brent@GMATPrepNow posted a reply to The table above shows the number of students in a certain in the Data Sufficiency forum
“ASIDE: Since the diagram closely resembles a Double Matrix Method diagram, I''ll treat it as such. Target question: What is the total number of students in the class? Statement 1: Of the boys in the class, 15 are studying biology. Add this information to our diagram to get: ...”
July 8, 2019
Max@Math Revolution posted a new topic called Let f(n) be the number of positive factors of n. What is min in the Problem Solving forum
“[GMAT math practice question] Let f(n) be the number of positive factors of n. What is minimum x satisfying f(420)*f(x)=96? A. 4 B. 6 C. 8 D. 10 E. 12”
July 8, 2019
Max@Math Revolution posted a new topic called x, y are two different positive integers greater than 6. Wha in the Data Sufficiency forum
“[GMAT math practice question] x, y are two different positive integers greater than 6. What are x and y? 1) x * y =1008 2) the greatest common divisor of x and y is 6”
July 8, 2019
Max@Math Revolution posted a reply to The vertices of a regular pentagon are to be colored using f in the Problem Solving forum
“=> The number of ways to choose 5 colors out of 6 colors is 6C5 = 6. The number of circular permutations of the 5 colors is (5-1)! = 4! = 24. Thus, 6*24 = 144 different colorings of the pentagon are possible. Therefore, D is the answer. Answer: D ”
July 8, 2019
Max@Math Revolution posted a reply to What is the number of solutions of x = |x-|30-2x||? in the Problem Solving forum
“=> The equation x = |x-|30-2x|| is equivalent to x = |x-2|x-15|| If x ≥ 15, then x = |x-2|x-15|| or x = | x – 2(x-15) | = | x – 2x + 30 | = | -x + 30 | = | x – 30 | If x ≥ 30, then x = | x – 30 | = x – 30 or 0 = -30, which doesn’t make sense. If 15 ≤ x < 30, then x = ...”
July 8, 2019
Max@Math Revolution posted a reply to Is 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 ...”
July 8, 2019
Max@Math Revolution posted a reply to m and n are positive integers. Is m^2 + n^2 is divisible by 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 ...”
July 8, 2019
Brent@GMATPrepNow posted a reply to The table above shows the number of students in a certain in the Data Sufficiency forum
“ASIDE: Since the diagram closely resembles a Double Matrix Method diagram, I''ll treat it as such. Target question: What is the total number of students in the class? Statement 1: Of the boys in the class, 15 are studying biology. Add this information to our diagram to get: ...”
July 7, 2019
Brent@GMATPrepNow posted a reply to If x is a positive integer such that x^2 + 5x − 14 = 0, wh in the Problem Solving forum
“GIVEN: x² + 5x − 14 = 0 Factor: (x + 7)(x - 2) = 0 So, EITHER x = -7 OR x = 2 Since we''re told x is POSITIVE, the correct answer is D Cheers, Brent”
July 7, 2019
Brent@GMATPrepNow posted a reply to What is the value of n in the equation: - 25 + 19 + n = s ? in the Data Sufficiency forum
“ Given: -25 + 19 + n = s Simplify: -6 + n = s Add 6 to both sides to get: n = s + 6 Target question: What is the value of n? Statement 1: s = 2 We already know that n = s + 6 Replace s with 2 to get: n = 2 + 6 = 8 The answer to the target question is n = 8 Since we can answer the ...”
July 6, 2019
Brent@GMATPrepNow posted a reply to The price of a phone call consists of a standard connection in the Problem Solving forum
“BTW, you posted the same question in January: https://www.beatthegmat.com/the-price-of-a-phone-call-consists-of-a-standard-connection-t305974.html Cheers, Brent”
July 5, 2019
Brent@GMATPrepNow posted a reply to The price of a phone call consists of a standard connection in the Problem Solving forum
“Let C = price of connection fee Let M = the price PER MINUTE A 10-minute call costs $2.90 We can write: C + 10M = 2.90 A 16-minute call costs$4.40. We can write: C + 16M = 4.40 How much does a 13-minute call cost? So far, we have: C + 10M = 2.90 C + 16M = 4.40 ONE (slower) ...”
July 5, 2019
Max@Math Revolution posted a new topic called The vertices of a regular pentagon are to be colored using f in the Problem Solving forum
“[GMAT math practice question] The vertices of a regular pentagon are to be colored using five different colors. In how many ways can the pentagon’s vertices be colored if the 5 colors are to be chosen from a palette of 6 different colors? A. 64 B. 96 C. 108 D. ...”
July 5, 2019
Max@Math Revolution posted a reply to A palindrome, such as 12321, is a number that remains the sa in the Problem Solving forum
“=> Palindromes between 1000 and 10,000 have the form ABBA. When we check divisibility by 4, we need only check the divisibility of BA by 4. The values of BA which are divisible by 4 are 04, 08, 12, 16, 24, 28, 32, 36, 44, 48, 52, 56, 64, 68, 72, 76, 84, 88, 92, and 96 (note that 20, 40, 60, ...”
July 5, 2019
Max@Math Revolution posted a new topic called Is x > 1? in the Data Sufficiency forum
“[GMAT math practice question] Is x > 1? 1) x^2 > x|x| 2) x|x| > x”
July 5, 2019
Max@Math Revolution posted a reply to k, m and n are positive integers. Is their average equal to 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 ...”
July 5, 2019
Brent@GMATPrepNow posted a reply to A certain family has 3 sons: Richard is 6 years older than in the Problem Solving forum
“We can also solve this with 1 variable David is 8 years older than Scott Let x = Scott''s age NOW So, x + 8 = David''s age NOW Richard is 6 years older than David If x + 8 = David''s age NOW, then... (x + 8) + 6 = Richard''s age NOW In other words, x + 14 = Richard''s age NOW In in 8 ...”
July 4, 2019
Max@Math Revolution posted a new topic called What is the number of solutions of x = |x-|30-2x||? in the Problem Solving forum
“[GMAT math practice question] What is the number of solutions of x = |x-|30-2x||? A. 0 B. 1 C. 2 D. 3 E. 4”
July 4, 2019
Max@Math Revolution posted a reply to The average of the numbers 1, 2, 3, … , 98, 99 and x is 10 in the Problem Solving forum
“=> ( 1 + 2 + 3 + … + 98 + 99 + x ) / 100 = 100x. So, 1 + 2 + 3 + … + 98 + 99 + x = 10000x, and 1 + 2 + 3 + … + 99 = 9999x. It follows that 9999x = 99*100/2 = 4950, and x = 4950 / 9999 = 550 / 1111 = 50 / 101. Therefore, the answer is D. Answer: D”
July 4, 2019
Max@Math Revolution posted a new topic called m and n are positive integers. Is m^2 + n^2 is divisible by in the Data Sufficiency forum
“[GMAT math practice question] m and n are positive integers. Is m^2 + n^2 is divisible by 3? 1) m = 1234 2) n = 4321”
July 4, 2019
Max@Math Revolution posted a reply to p and q are different positive integers. What is the remaind 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 ...”
July 4, 2019
Brent@GMATPrepNow posted a reply to When the positive integer x is divided by 11, the quotient in the Problem Solving forum
“A fast approach is to find a value of x that meets the given conditions. When the positive integer x is divided by 11, the quotient is y and the remainder 3. When x is divided by 19, the remainder is also 3.... Notice that x = 3 meets the above conditions. 3 divided by 11 = 0 with remainder ...”
July 3, 2019
Brent@GMATPrepNow posted a reply to A palindrome, such as 12321, is a number that remains the sa in the Problem Solving forum
“If a number is divisible by 4, then the number created by the last 2 digits is divisible by 4. For example, we know that 76512, 311,244 and 2128 are divisible by 4 because 12, 44, and 28 are divisible by 4 So, the last 2 digits of the 4-digit palindromes must be 00, 04, 08, 12, . . . , 92 or ...”
July 3, 2019
Max@Math Revolution posted a new topic called A palindrome, such as 12321, is a number that remains the sa in the Problem Solving forum
“[GMAT math practice question] A palindrome, such as 12321, is a number that remains the same when its digits are reversed. How many 4-digit palindromes are divisible by 4? A. 10 B. 20 C. 25 D. 28 E. 30”
July 3, 2019
Max@Math Revolution posted a reply to A palindrome, such as 12321, is a number that remains the sa in the Problem Solving forum
“=> Let x = ABA and x + 32 = CDDC. Then CDDC = ABA + 32 Since CDDC has a thousands digit, we must have A = 9. Then the units digit of CDDC is equal to the units digit of A + 2 = 11. And, looking at the tens digits, we must have B + 3 + 1 ≥ 10. Therefore, B ≥ 6. The possible values ...”
July 3, 2019
Max@Math Revolution posted a new topic called k, m and n are positive integers. Is their average equal to in the Data Sufficiency forum
“[GMAT math practice question] k, m and n are positive integers. Is their average equal to their median? 1) The median of k, m and n is 11. 2) The range of k, m and n is 13”
July 3, 2019
Max@Math Revolution posted a reply to If k, m and n are positive integers, what is the value of km 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 ...”
July 3, 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. ...”
July 3, 2019
Brent@GMATPrepNow posted a reply to x, y and z are all unique numbers. If x is chosen randomly in the Problem Solving forum
“Thanks Ian. Not sure how I missed "unique." Thanks for clarifying. Cheers, Brent”
July 2, 2019
Brent@GMATPrepNow posted a reply to x, y and z are all unique numbers. If x is chosen randomly in the Problem Solving forum
“Are the numbers chosen with or without replacement? For example, can y and z both be 23?”
July 2, 2019
Max@Math Revolution posted a new topic called The average of the numbers 1, 2, 3, … , 98, 99 and x is 100x in the Problem Solving forum
“[GMAT math practice question] The average of the numbers 1, 2, 3, … , 98, 99 and x is 100x. What is the value of x? A. 1/10 B. 2/11 C. 5/51 D. 50/101 E. 50/201”
July 2, 2019
Max@Math Revolution posted a new topic called p and q are different positive integers. What is the remaind in the Data Sufficiency forum
“[GMAT math practice question] p and q are different positive integers. What is the remainder when p^2 + q^2 is divided by 4? 1) p and q are prime numbers. 2) p and q are not consecutive integers.”
July 2, 2019
Brent@GMATPrepNow posted a reply to How many two-digit whole numbers yield a remainder of 1 when in the Problem Solving forum
“...two-digit whole numbers yield a remainder of 1... Possible values are: 11, 21, 31, 41, 51, 61, 71, 81, and 91 ...and also yield a remainder of 1 when divided by 6 Take each value from 11, 21, 31, 41, 51, 61, 71, 81, and 91, and see which ones leave a remainder of 1 when divided by 6 11, 21, ...”
July 1, 2019
Max@Math Revolution posted a new topic called A palindrome, such as 12321, is a number that remains the sa in the Problem Solving forum
“[GMAT math practice question] A palindrome, such as 12321, is a number that remains the same when its digits are reversed. The numbers x and x+32 are three-digit and four-digit palindromes, respectively. What is the sum of the digits of x? A. 18 B. 24 C. 28 D. 32 ...”
July 1, 2019
Max@Math Revolution posted a new topic called If k, m and n are positive integers, what is the value of km in the Data Sufficiency forum
“[GMAT math practice question] If k, m and n are positive integers, what is the value of kmn? 1) k^4mn = 240 2) m = 3”
July 1, 2019
Max@Math Revolution posted a reply to x & y is defined as |x-y|. Which of following is (are) t in the Problem Solving forum
“=> Statement I. x & y = | x – y | = | y – x | = y & x. Statement I is true. Statement II 2x & 2y = | 2x – 2y | = 2| x – y | = 2 (x&y). Statement II is true. Statement III x & x = | x – x | = 0. Statement III is true. Therefore, E is the answer. ...”
July 1, 2019
Max@Math Revolution posted a reply to Both roots of the quadratic equation x^2-39x+a = 0 are prime in the Problem Solving forum
“=> Assume p and q are roots of x^2-39x+a = 0. Then (x-p)(x-q) = x^2 –(p+q)x + pq = x^2-39x+a = 0 So, p + q = 39 and pq = a. Since p and q are prime numbers and p + q = 39 is an odd number, one of p and q is an even prime number. Since the only even prime number is 2, one of p and q must ...”
July 1, 2019
Max@Math Revolution posted a reply to If x > y, then what is the median of x, y, 9 and 9? 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 ...”
July 1, 2019
Max@Math Revolution posted a reply to For positive integers m and n, is 3+3^2+3^3+….+3^{mn+1} di 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 ...”
July 1, 2019
Brent@GMATPrepNow posted a reply to Is it true that a > b? in the Data Sufficiency forum
“Target question: Is a > b? Statement 1: 2a > 2b Divide both sides by 2 to get: a > b The answer to the target question is YES, a IS greater than b Since we can answer the target question with certainty, statement 1 is SUFFICIENT Statement 2: a + c > b + c Subtract b from ...”
June 30, 2019
Brent@GMATPrepNow posted a reply to If sequence S has 120 terms, what is the 105th term of S? in the Data Sufficiency forum
“Target question: What is the 105th term of S? Given: Sequence S has 120 terms Statement 1: The first term of S is −8. We have no information about the nature of the sequence. So, knowing the value of term 1 won''t help is determine the value of term 105 Since we cannot answer the ...”
June 30, 2019
Brent@GMATPrepNow posted a reply to If a certain wheel turns at a constant rate of $$x$$ in the Problem Solving forum
“We can solve the question using equivalent ratios Wheel turns at a constant rate of x revolutions per minute We can also say the wheel turns at a constant rate of x revolutions per 60 seconds In other words, # of revolutions/seconds elapsed = x/60 How many revolutions will the wheel make in ...”
June 29, 2019
Brent@GMATPrepNow posted a reply to Leona bought a 1-year, $10,000 certificate of deposit that in the Problem Solving forum “If the interest is at an ANNUAL rate of 8 percent compounded semiannually, then EVERY SIX MONTHS, we add 4% interest to the certificate. No need to apply the compound interest formula. It''s just as fast to make the 2 calculations. After 6 months, the value of the certificate =$10,000 + (4% of ...”
June 28, 2019
Max@Math Revolution posted a new topic called x & y is defined as |x-y|. Which of following is (are) true? in the Problem Solving forum
“[GMAT math practice question] x & y is defined as |x-y|. Which of following is (are) true? I. x & y = y & x II. 2x & 2y = 2(x&y) III. x & x = 0 A. I only B. II only C. III only D. I and II only E. I, II, III”
June 28, 2019
Max@Math Revolution posted a reply to -2 ≤ x ≤ -1 and 1 ≤ y ≤ 2. What is the greatest poss in the Problem Solving forum
“=> (x+y)/x = x/x + y/x = 1 + y/x Since -2 ≤ x ≤ -1 and 1 ≤ y ≤ 2, we have -2 ≤ y/x ≤ -1/2 and -1 ≤ 1 + y/x ≤ 1/2. Thus, the greatest possible value of (x+y)/x is ½. Therefore, the answer is D. Answer: D ”
June 28, 2019
Max@Math Revolution posted a new topic called If x > y, then what is the median of x, y, 9 and 9? in the Data Sufficiency forum
“[GMAT math practice question] If x > y, then what is the median of x, y, 9 and 9? 1) The average (arithmetic mean) of x and y is 9. 2) The average of x, y and 18 is 12.”
June 28, 2019
Max@Math Revolution posted a reply to The data set X has 6 elements. Its mean is 0 and its standar 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 ...”
June 28, 2019
Brent@GMATPrepNow posted a reply to A computer routine was developed to generate two numbers, in the Problem Solving forum
“Check each answer choice... (A) (99, 10) √100 = 10 So, √99 is LESS THAN 10 In other words, 10 is GREATER THAN √99 So, answer choice A breaks the rule that says the second number must be less than or equal to the square root of the first" Answer: A Cheers, Brent”
June 27, 2019
Max@Math Revolution posted a new topic called Both roots of the quadratic equation x^2-39x+a = 0 are prime in the Problem Solving forum
“[GMAT math practice question] Both roots of the quadratic equation x^2-39x+a = 0 are prime numbers. How many different possible values of a are there? A.1 B. 2 C. 3 D. 4 E. 5”
June 27, 2019
Max@Math Revolution posted a reply to What is the average (arithmetic mean) of all 5-digit numbers in the Problem Solving forum
“=> There are 5! = 120 different numbers of this form. Next, we find the sum of all numbers of this form. Let’s start by considering the numbers with 1 in each position. There are 4! = 24 numbers with 1 in the ten-thousands digit (these contribute 24 x 1 x 10000 to the sum), 24 ...”
June 27, 2019
Max@Math Revolution posted a new topic called For positive integers m and n, is 3+3^2+3^3+….+3^{mn+1} divi in the Data Sufficiency forum
“[GMAT math practice question] For positive integers m and n, is 3+3^2+3^3+….+3^{mn+1} divisible by 6? 1) m^2 + n^2 has remainder 1 when it is divided by 4. 2) m / n is an integer.”
June 27, 2019
Max@Math Revolution posted a reply to m is an odd integer. If m^3n^4=432, what is the value of 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. Since we ...”
June 27, 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. ...”
June 27, 2019
Brent@GMATPrepNow posted a reply to If Lucy walks to work at a rate of 4 miles per hour, but she in the Problem Solving forum
“Let d = distance from home to work Average speed = (total distance traveled)/(total travel time) total distance traveled = d + d = 2d total travel time = travel time TO work + travel time FROM work time = distance/speed We get: total travel time = d/4 + d/6 = 3d/12 + 2d/12 = ...”
June 26, 2019
Brent@GMATPrepNow posted a reply to Right triangle PQR is to be constructed in the xy-plane so in the Problem Solving forum
“Take the task of building triangles and break it into stages. Stage 1: Select any point where the right angle will be (point P). The point can be selected from a 10x11 grid. So, there 110 points to choose from. This means that stage 1 can be completed in 110 ways. Stage 2: Select a point ...”
June 26, 2019
Max@Math Revolution posted a new topic called -2 ≤ x ≤ -1 and 1 ≤ y ≤ 2. What is the greatest possible val in the Problem Solving forum
“[GMAT math practice question] -2 ≤ x ≤ -1 and 1 ≤ y ≤ 2. What is the greatest possible value of ( x + y ) / x? A. -1 B. –1/2 C. 0 D. 1/2 E. 1”
June 26, 2019
Max@Math Revolution posted a reply to A factory has two machines. Machine X can produce 200 pins p in the Problem Solving forum
“=> In order to minimize the number of hours that the two machines work together, the more efficient machine Y should work for the entire day. Thus, Y works for 8 hours and produces 8 * 500 = 4,000 pins. There are 1,000 pins remaining for machine X to produce. This takes 1,000/200 = 5 ...”
June 26, 2019
Max@Math Revolution posted a new topic called The data set X has 6 elements. Its mean is 0 and its standar in the Data Sufficiency forum
“[GMAT math practice question] The data set X has 6 elements. Its mean is 0 and its standard deviation is d, where d is not zero. When we add a new data element x to the set X, D is the standard deviation of the new set of 7 elements. Is D < d? 1) |x| < d 2) x = 0”
June 26, 2019
Max@Math Revolution posted a reply to If a and b are positive integers, is a^2-b^2 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 ...”
June 26, 2019
Brent@GMATPrepNow posted a reply to If y= 4 + (x - 3)^2, then y is lowest when in the Problem Solving forum
“KEY CONCEPT: In order to minimize the value of y, we must minimize the value of (x -3)² We know that (some number)² ≥ 0 So, the SMALLEST possible value of (some number)² is 0 Likewise, the SMALLEST possible value of (x -3)² is 0 (x -3)² = 0 when x = 3 Answer: D Cheers, Brent”
June 25, 2019
Brent@GMATPrepNow posted a reply to In the figure shown, what is the value of x? in the Data Sufficiency forum
“The diagram (aka figure) is missing.”
June 25, 2019
Brent@GMATPrepNow posted a reply to For integers x and y, which of the following MUST be an in the Problem Solving forum
“One approach: The question is asking us to determine which expression MUST be an integer for ALL integer values of x and y. So, let''s TEST a pair of values. Let''s plug in x = 1 and y = 1 If an expression evaluates to be a non-integer, we can ELIMINATE that answer choice. We get... ...”
June 25, 2019
Brent@GMATPrepNow posted a reply to A certain basketball team that has played 2/3 of its games in the Problem Solving forum
“Given: The team has played 2/3 of its games. The team has played 20 games. If 2/3 of the total number of games = 20, then the total number of games = 30. This means that there are 10 games remaining. We want the team to win at least 3/4 of its games. 3/4 of 30 = 22.5 So, in order to ...”
June 25, 2019
Max@Math Revolution posted a new topic called What is the average (arithmetic mean) of all 5-digit numbers in the Problem Solving forum
“[GMAT math practice question] What is the average (arithmetic mean) of all 5-digit numbers that can be formed using each of the digits 1, 3, 5, 7 and 9 exactly once? A. 48000 B. 50000 C. 54000 D. 55555 E. 56000”
June 25, 2019
Max@Math Revolution posted a new topic called m is an odd integer. If m^3n^4=432, what is the value of n? in the Data Sufficiency forum
“[GMAT math practice question] m is an odd integer. If m^3n^4=432, what is the value of n? 1) n is positive. 2) n is an integer.”
June 25, 2019
Max@Math Revolution posted a new topic called A factory has two machines. Machine X can produce 200 pins p in the Problem Solving forum
“[GMAT math practice question] A factory has two machines. Machine X can produce 200 pins per hour and machine Y can produce 500 pins per hour. At least one machine is in operation throughout the 8-hour work day. The factory must produce 5,000 pins every day. What is the least possible number of ...”
June 24, 2019
Max@Math Revolution posted a new topic called If a and b are positive integers, is a^2-b^2 divisible by 4? in the Data Sufficiency forum
“[GMAT math practice question] If a and b are positive integers, is a^2-b^2 divisible by 4? 1) a+b is divisible by 4 2) a^2+b^2 has remainder 2 when it is divided by 4”
June 24, 2019
Max@Math Revolution posted a reply to 5 boys and 5 girls randomly select seats around a circular t in the Problem Solving forum
“=> The easiest way to solve this problem is to find the number of arrangements satisfying the complementary condition that boys and girls are arranged alternately around the table, and subtract this from the total number of arrangements of the boys and girls. The number of arrangements of ...”
June 24, 2019
Max@Math Revolution posted a reply to What is the value of 1 / (√2+√1) + 1 / (√3+√2) + 1/( in the Problem Solving forum
“=> We rationalize the denominator of each fraction to give 1 / (√2+ √1) + 1 / (√3+ √2) + 1/( √4+ √3) + … + 1/( √25+ √24) = (√2-√1)/[(√2+√1)(√2-√1)] + (√3-√2)/[(√3+√2) (√3-√2)] + (√4-√3)/[(√4+√3) (√4-√3)] + … + ...”
June 24, 2019
Max@Math Revolution posted a reply to What is the greatest common divisor of positive integers m a 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 ...”
June 24, 2019
Max@Math Revolution posted a reply to a, b, c and d are integers. Is abcd + abc + ab + a an even 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 ...”
June 24, 2019
Brent@GMATPrepNow posted a reply to If 2xy + z = 9, what is the value of the positive integer z? in the Data Sufficiency forum
“ Given: 2xy + z = 9 Target question: What is the value of the positive integer z? Statement 1: xyz - z² = 0 Factor to get: z(xy - z) = 0 This means that EITHER z = 0 OR xy - z = 0 HOWEVER, we''re told that z is a POSITIVE integer, which means z ≠0 So, it must be the case that xy - ...”
June 22, 2019
Brent@GMATPrepNow posted a reply to What is the perimeter of isosceles triangle MNP? in the Data Sufficiency forum
“Target question: What is the perimeter of isosceles triangle MNP? Statement 1: MN = 16 No idea about the other 2 sides Statement 1 is NOT SUFFICIENT Statement 2: NP = 20 No idea about the other 2 sides Statement 2 is NOT SUFFICIENT Statements 1 and 2 combined Since we have an ...”
June 22, 2019
Brent@GMATPrepNow posted a reply to f x and y are positive, what is the value of y ? in the Data Sufficiency forum
“Target question: What is the value of y? Given: x and y are positive Statement 1: xy is the square of an integer. There are several values of x and y that satisfy this condition. Here are two: Case a: x = 1 and y = 1. Here xy = (1)(1) = 1, which is the square of an integer. In this ...”
June 21, 2019
Brent@GMATPrepNow posted a reply to Which of the following is an integer? I. 12! / 6! II. 12! / in the Problem Solving forum
“I. 12!/6! = (12)(11)(10)(9)(8)(7)(6)(5)(4)(3)(2)(1)/(6)(5)(4)(3)(2)(1) = (12)(11)(10)(9)(8)(7) = some integer II. 12!/8! = (12)(11)(10)(9)(8)(7)(6)(5)(4)(3)(2)(1)/(8)(7)(6)(5)(4)(3)(2)(1) = (12)(11)(10)(9) = some integer III. 12!/7!5! = ...”
June 21, 2019
Max@Math Revolution posted a new topic called 5 boys and 5 girls randomly select seats around a circular t in the Problem Solving forum
“[GMAT math practice question] 5 boys and 5 girls randomly select seats around a circular table that seats 10. What is the probability that two girls will sit next to one another? A. 11/24 B. 23/24 C. 23/48 D. 47/48 E. 125/126”
June 21, 2019
Max@Math Revolution posted a reply to What is the value of the following sum? 1/(1*2) + 1/(2*3) + in the Problem Solving forum
“=> Recall that 1/[n*(n+1)] = 1/n – 1/(n+1). So, 1/(1*2) + 1/(2*3) + 1/(3*4) + 1/(4*5) + 1/(5*6) = (1/1 – 1/2) + (1/2 – 1/3) + (1/3 – 1/4) + (1/4 – 1/5) + (1/5 – 1/6) = 1/1 – 1/6 = 5/6 Therefore, the answer is D. Answer: D ”
June 21, 2019
Max@Math Revolution posted a new topic called What is the greatest common divisor of positive integers m a in the Data Sufficiency forum
“[GMAT math practice question] What is the greatest common divisor of positive integers m and n? 1) m and n are different prime numbers 2) m and n are consecutive integers”
June 21, 2019
Max@Math Revolution posted a reply to a, b and c are positive numbers. Is a>b-c? 1) a, b, and 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 ...”
June 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. ...”
June 21, 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 ...” June 20, 2019 Brent@GMATPrepNow posted a reply to In how many different ways can 3 fiction books and 3 in the Problem Solving forum “Take the task of arranging the 6 books and break it into stages. Stage 1: Arrange the 3 fiction books in a row We can arrange n unique objects in n! ways So, we can arrange the 3 books in 3! ways (= 6 ways) So, we can complete stage 1 in 6 ways Stage 2: Arrange the 3 non-fiction books in ...” June 20, 2019 Max@Math Revolution posted a new topic called What is the value of 1 / (√2+√1) + 1 / (√3+√2) + 1/(√4+√3) + in the Problem Solving forum “[GMAT math practice question] What is the value of 1 / (√2+√1) + 1 / (√3+√2) + 1/(√4+√3) + … + 1/(√25+√24)? A.1 B. 2 C. 3 D. 4 E. 5” June 20, 2019 Max@Math Revolution posted a reply to How many arrangements of the letters A, C, C, E, N, T includ in the Problem Solving forum “=> The easiest way to solve this problem is to find the number of arrangements satisfying the complementary condition that there is no letter between the two C’s and subtract this from the total number of arrangements of the letters. The best approach to solving probability or counting ...” June 20, 2019 Max@Math Revolution posted a new topic called a, b, c and d are integers. Is abcd + abc + ab + a an even in the Data Sufficiency forum “[GMAT math practice question] a, b, c and d are integers. Is abcd + abc + ab + a an even number? 1) abc is an odd integer 2) bcd is an odd integer” June 20, 2019 Max@Math Revolution posted a reply to If |2x|>|3y|, is x >y? 1) x>0 2) y>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 ...” June 20, 2019 Brent@GMATPrepNow posted a reply to Data sufficiency in the GMAT Math forum “Take: y = 1 + 1/x Rewrite as: y = x/x + 1/x Simplify: y = (x + 1)/x So, we''re looking for an answer choice that can be expressed as a fraction in which the numerator is 1 greater than the denominator. Answer: E Cheers, Brent” June 19, 2019 Brent@GMATPrepNow posted a reply to If is n is multiple of 5, and n=p^2*q where p and q are prim in the Problem Solving forum “Let''s test some values that satisfy the given conditions (n is multiple of 5, and n = p²q, where p and q are prime numbers) How about: p = 2 and q = 5. In this case, n = (2²)(5) = 20, and 20 is a multiple of 5, which satisfies the given condition. Now plug p = 2 and q = 5 into the ...” June 19, 2019 Brent@GMATPrepNow posted a new topic called If 3 different integers are randomly selected from the set { in the Problem Solving forum “If 3 different integers are randomly selected from the set {1, 2, 3, 4, 5, 6}, what is the probability that a triangle can be constructed so that its 3 sides have the lengths of the 3 selected numbers? A) 0.25 B) 0.3 C) 0.35 D) 0.40 E) 0.45 Source: www.gmatprepnow.com Difficulty level: ...” June 19, 2019 Brent@GMATPrepNow posted a reply to A certain zoo has mammal and reptiles and birds, and no in the Data Sufficiency forum “Target question: How many birds are in the zoo? Given: The ratio of mammals to reptiles to birds is 11: 8:5. Given this ratio, we could say that there are: 11x mammals 8x reptiles 5x birds for some value of x. Statement 1: there are twelve more mammals in the zoo than there are ...” June 19, 2019 Max@Math Revolution posted a new topic called What is the value of the following sum? 1/(1*2) + 1/(2*3) + in the Problem Solving forum “What is the value of the following sum? 1/(1*2) + 1/(2*3) + 1/(3*4) + 1/(4*5) + 1/(5*6) A. 2/3 B. 3/4 C. 4/5 D. 5/6 E. 1” June 19, 2019 Max@Math Revolution posted a reply to How many rectangles can be formed by connecting the grid poi in the Problem Solving forum “Answer: E Each collection of two horizontal and two vertical lines forms a rectangle. The number of ways to choose 2 vertical lines out of 7 lines is 7C2, and the number of ways to choose 2 horizontal lines out of 6 lines is 6C2. Thus, the total number of rectangles is is 7C2 * 6C2.= ...” June 19, 2019 Max@Math Revolution posted a new topic called a, b and c are positive numbers. Is a>b-c? 1) a, b, and c a in the Data Sufficiency forum “a, b and c are positive numbers. Is a>b-c? 1) a, b, and c are the lengths of three different sides of a triangle 2) a^2+b^2=c^2” June 19, 2019 Max@Math Revolution posted a reply to Is x<0? 1) x^3+1<0 2) x^3+2x^2+x+2=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. Since we have 1 ...” June 19, 2019 Brent@GMATPrepNow posted a reply to If x, y and z are three different non-negative integers, whi in the Problem Solving forum “Nice work, Mitch! I created this question to illustrate the importance of checking the answer choices each time you analyze one of the statements. Here’s why: Once we know that statement i COULD be true (it''s true when x = 0, y = 1 and z = 2), we should check the answer choices…. ...” June 18, 2019 Brent@GMATPrepNow posted a reply to A certain machine produces 1,000 units of product P per hour in the Problem Solving forum “A certain machine produces 1,000 units in 1 hour So, the machine produces 24,000 units in 24 hours In other words, the machine produces 24,000 units in 1 DAY So, the machine produces (24,000)(7) units in 7 DAYS (20,000)(7) = 140,000 So, (24,000)(7) = some number greater than 140,000 ...” June 18, 2019 Brent@GMATPrepNow posted a new topic called If x, y and z are three different non-negative integers, whi in the Problem Solving forum “If x, y and z are three different non-negative integers, which of the following COULD be true? i) |x−y| = |x+y| = |y−z| ii) x^y = y^z iii) x³ + y³ = z³ A) i only B) ii only C) iii only D) i and ii E) i and iii Source; www.gmatprepnow.com Difficulty level: 700+ Answer: D” June 18, 2019 Max@Math Revolution posted a new topic called How many arrangements of the letters A, C, C, E, N, T includ in the Problem Solving forum “How many arrangements of the letters A, C, C, E, N, T include at least one letter between the two C’s? A. 60 B. 120 C. 240 D. 360 E. 720” June 18, 2019 Max@Math Revolution posted a new topic called If |2x|>|3y|, is x >y? 1) x>0 2) y>0 in the Data Sufficiency forum “If |2x|>|3y|, is x >y? 1) x>0 2) y>0” June 18, 2019 Brent@GMATPrepNow posted a reply to If p is an integer greater than 1, is p a prime number? in the Data Sufficiency forum “ Given: p is an integer greater than 1 Target question: Is p a prime number? Statement 1: p is a factor of 13 13 has exactly two factors: 1 and 13 Since p > 1, we KNOW that p = 13 (which is prime) The answer to the target question is YES, p IS prime Since we can answer the target ...” June 17, 2019 Brent@GMATPrepNow posted a reply to How many ways are there to arrange the letters in the word in the Problem Solving forum “------------ASIDE----------------- When we want to arrange a group of items in which some of the items are identical, we can use something called the MISSISSIPPI rule. It goes like this: If there are n objects where A of them are alike, another B of them are alike, another C of them are alike, ...” June 17, 2019 Brent@GMATPrepNow posted a reply to If |2x + 5| = |3x − 2|, which of the following is a possib in the Problem Solving forum “If |x| = |y|, then either x = y OR x = -y GIVEN: |2x + 5| = |3x − 2| So, EITHER 2x + 5 = 3x − 2 OR 2x + 5 = -(3x − 2) Let''s solve each equation... Take: 2x + 5 = 3x − 2 We get: 5 = x - 2 Solve: x = 7 Check answer choices.....x = 7 is not there. Try the other equation: Take: ...” June 17, 2019 Brent@GMATPrepNow posted a reply to Is h^2 = h? in the Data Sufficiency forum “Target question: Is h² = h? Statement 1: h + h = h Subtract h from both sides to get: h = 0 If h = 0, then h² = h becomes 0² = 0 (WORKS!) The answer to the target question is YES, h² = h Since we can answer the target question with certainty, statement 1 is SUFFICIENT Statement 2: ...” June 17, 2019 Brent@GMATPrepNow posted a reply to Is z > 0.5? in the Data Sufficiency forum “Target question: Is z > 0.5 ? SCAN the statements to see we can jump straight to.... Statements 1 and 2 combined There are infinitely-many values of z that satisfy BOTH statements. . Here are two: Case a: z = 0.6. In this case, the answer to the target question is YES, z IS greater ...” June 17, 2019 Brent@GMATPrepNow posted a reply to What is the value of x? in the Data Sufficiency forum “Target question: What is the value of x? Statement 1: 5x + 3y = 15 Since this is a linear equation with infinitely many solutions. Here are two: Case a: x = 3 and y = 0. In this case, the answer to the target question is x = 3 Case b: x = 0 and y = 5. In this case, the answer to the target ...” June 17, 2019 Brent@GMATPrepNow posted a reply to If the average (arithmetic mean) of seven consecutive in the Problem Solving forum “Another approach: For any set of consecutive integers, mean = median. So, in this case, mean = median = k + 2 So, the three values that come AFTER k + 2 are k+3, k+4, and k+5 And the three values that come BEFORE k + 2 are k-1, k, k+1, k+2, k+3, k+4, k+5 The product of the greatest and ...” June 17, 2019 Max@Math Revolution posted a new topic called How many rectangles can be formed by connecting the grid poi in the Problem Solving forum “How many rectangles can be formed by connecting the grid points from the figure above? (Diagonal connection of grid points is not permitted) https://i.postimg.cc/LJdQ6038/table-1.jpg A. 72 B. 96 C. 108 D. 192 E. 315” June 17, 2019 Max@Math Revolution posted a new topic called Is x<0? 1) x^3+1<0 2) x^3+2x^2+x+2=0 in the Data Sufficiency forum “Is x<0? 1) x^3+1<0 2) x^3+2x^2+x+2=0” June 17, 2019 Max@Math Revolution posted a reply to What is the remainder when 7^100 is divided by 50? in the Problem Solving forum “When we compute with remainders, we can either take the remainder first and then compute, or compute first and then take the remainder. 7^2 = 49 has remainder 49 when it is divided by 50. When numbers are divided by 50, a remainder of 49 can be thought of as a remainder of -1. Therefore, ...” June 17, 2019 Max@Math Revolution posted a reply to At how many points does the parabola y=f(x)=ax^2+bx+c (a≠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 step of ...” June 17, 2019 Max@Math Revolution posted a reply to [x] is the greatest integer less than or equal to x. What is in the Problem Solving forum “[x] means round down. π^2 – 10 ≈ (3.14)^2 – 10 ≈ 9.86 – 10 = -0.14. Therefore, [-0.14] = -1 since -1 is the greatest integer less than or equal to -0.14. Therefore, the answer is C.” June 17, 2019 Max@Math Revolution posted a reply to If p and q are prime numbers, what is the number of the diff 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 ...” June 17, 2019 Brent@GMATPrepNow posted a reply to Of the first three dozen cookies baked at a bake shop on a in the Data Sufficiency forum “ Given: Of the first three dozen (36) cookies baked at a bake shop on a certain day, 1/3 were chocolate chip cookies. 1/2 of the remaining cookies that were baked that day were chocolate chip cookies, 1/3 of 36 = 12. So, 12 chocolate cookies were baked in the first round of baking. Let x = ...” June 15, 2019 Brent@GMATPrepNow posted a reply to List $$K$$ consists of seven numbers. Is the average in the Data Sufficiency forum “Target question: Is the average (arithmetic mean) of the seven numbers negative? Statement 1: Four of the seven numbers in list K are negative. There are several scenarios that satisfy statement 1. Here are two: Case a: List K = {-10, -10, -10, -10, 1, 1, 1}. Average = sum/7 = -37/7. The ...” June 15, 2019 Brent@GMATPrepNow posted a reply to A set of 15 different integers has median of 25 and a range in the Problem Solving forum “Let''s tackle this one step at a time. First, we have 15 different integers. We can let these 15 spaces represent the 15 numbers written in ascending order: _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ If the median is 25, we can add this as the middle value: _ _ _ _ _ _ _ 25 _ _ _ _ _ _ _ Notice that 7 ...” June 15, 2019 Brent@GMATPrepNow posted a reply to 8, 5, x, 6 The median of the list of positive integers in the Problem Solving forum “Since there is an even number of values in the list, the median will be the AVERAGE of the two middlemost values (when all values are listed in ASCENDING order) Let''s the answer choices... A) If x = 3, then the values are {3, 5, 6, 8}, which means the median = (5 + 6)/2 = 5.5 NO GOOD. We ...” June 14, 2019 Brent@GMATPrepNow posted a reply to Will the first 10 volumes of a 20-volume encyclopedia fit in the Data Sufficiency forum “Target question: Will the first 10 volumes of a 20-volume encyclopedia fit upright in the bookrack shown above? Statement 1: x = 50 centimeters. We have no idea how THICK the first 10 volumes are. They COULD each be 1 mm thick, in which case the 10 volumes will easily fit in the 50 cm ...” June 14, 2019 Brent@GMATPrepNow posted a reply to For every integer $$k$$ from 1 to 10, inclusive the "k& in the Problem Solving forum “T = 1/2 - 1/4 + 1/8 - 1/16 + . . . Notice that we can rewrite this as T = (1/2 - 1/4) + (1/8 - 1/16) + . . . When you start simplifying each part in brackets, you''ll see a pattern emerge. We get... T = 1/4 + 1/16 + 1/64 + 1/256 + 1/1024 Now examine the last 4 terms: 1/16 + 1/64 + 1/256 + ...” June 14, 2019 Max@Math Revolution posted a new topic called What is the remainder when 7^100 is divided by 50? in the Problem Solving forum “What is the remainder when 7^100 is divided by 50? A. 1 B. 3 C. 5 D. 7 E. 49” June 14, 2019 Max@Math Revolution posted a new topic called At how many points does the parabola y=f(x)=ax^2+bx+c (a≠0) in the Data Sufficiency forum “At how many points does the parabola y=f(x)=ax^2+bx+c (a≠0) intersect the x-axis? 1) x=f(y) intersects the y-axis at two points. 2) y=f(x-1) intersects the x-axis at two points.” June 14, 2019 Max@Math Revolution posted a reply to It is known that (1.1)^{17} is approximately equal to 5.05. in the Problem Solving forum “Answer: D (1.1)^50 = (1.1)^(51 – 1) = (1.1)^51 / (1.1) = ((1.1)^17)^3 / (1.1) ≈ 5^3/1.1 = 125/1.1 ≈ 120 Therefore, the answer is D.” June 14, 2019 Max@Math Revolution posted a reply to If x and y are positive integers, are x and y consecutive? 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 ...” June 14, 2019 Brent@GMATPrepNow posted a reply to Jim is twice as old as Fred ... in the Problem Solving forum “I''ve added the answer choices.... TODAY''S AGES Today Jim is twice as old as Fred, and Sam is 2 years younger than Fred. Let x = Fred''s age TODAY So, 2x = Jim''s age TODAY And x - 2 = Sam''s age TODAY AGES FOUR YEARS AGO Let''s first determine Jim''s age and Sam''s age FOUR YEARS ...” June 13, 2019 Brent@GMATPrepNow posted a reply to in terms of k and m in the Problem Solving forum “One approach is to plug in values. Let$100 be the original price per share of Stock X Choose a "nice" value for k. How about k = 200 So, after a 200% increase, the new price per share = $300 Let$100 be the original earnings per share of Stock X Choose a "nice" ...”
June 13, 2019
Brent@GMATPrepNow posted a reply to cd? in the Data Sufficiency forum
“Target question: Is the product cd positive? Statement 1: 3c = -8d³ Divide both sides by d to get: 3c/d = -8d² Divide both sides by 3 to get: c/d = -8d²/3 Rewrite as: c/d = (-8/3)(d²) Since d² is greater than or equal to zero for all values of d, and since -8/3 is NEGATIVE, we can ...”
June 13, 2019
Brent@GMATPrepNow posted a reply to If f(x) = x^3 + 9, is f(x) positive? in the Data Sufficiency forum
“ Given: f(x) = x³ + 9 Target question: Is f(x) positive? Statement 1: x < −1 Let''s TEST some values. There are several values of x that satisfy statement 1. Here are two: Case a: x = -2. In this case, f(-2) = (-2)³ + 9 = (-8) + 9 = 1. So, the answer to the target question is ...”
June 13, 2019
Brent@GMATPrepNow posted a reply to In May Mrs Lee's earnings were 60 percent of the Lee family' in the Problem Solving forum
“Since we''re asked to find a PERCENT (and not an actual value), we can assign a nice value to the Lee family''s total income. In May Mrs Lee''s earnings were 60 percent of the Lee family''s total income Let''s say $100 = Lee family''s total income IN MAY This means$60 = Mrs Lee''s earnings ...”
June 13, 2019
Brent@GMATPrepNow posted a reply to Which of the following could be the median for a set of in the Problem Solving forum
“Since 20 < x < 80, we can see that, if we arrange the 5 numbers in ASCENDING order, we get two possible cases: case a: {x, 56, 86, 97, 98} case b: {56, x, 86, 97, 98} In both cases, the median is 86 Answer: B Cheers, Brent”
June 13, 2019
Max@Math Revolution posted a new topic called [x] is the greatest integer less than or equal to x. What is in the Problem Solving forum
“[x] is the greatest integer less than or equal to x. What is the value of [π^2 – 10]? A. -8 B. -7 C. -1 D. 0 E. 1”
June 13, 2019
Max@Math Revolution posted a new topic called If p and q are prime numbers, what is the number of the diff in the Data Sufficiency forum
“[GMAT math practice question] If p and q are prime numbers, what is the number of the different factors of p^2q^3? 1) pq=143 2) p and q are different”
June 13, 2019
Max@Math Revolution posted a reply to The quadrilateral ABCD is a kite. If AB = BC = 20, CD = DA = in the Problem Solving forum
“=> https://i.postimg.cc/kDMwGq04/6-13.png Let x and y be the lengths of DE and CE, repectively. From the right triangle CDE, we have CD^2 = x^2 + y^2 or x^2+y^2=225. From the right triangle BCD, we have BC^2 = (x+7)^2 + y^2 or (x+7)^2 + y^2 = 400. Subtracting the first equation from the ...”
June 13, 2019
Max@Math Revolution posted a reply to Is x^3-x^2+x-1 > 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 ...”
June 13, 2019
Brent@GMATPrepNow posted a reply to a, b and c are three distinct integers, greater than 1, such in the Problem Solving forum
“150 = (2)(3)(5)(5) There are three sets of 3 values (each greater than 1) that have a product of 150: {2, 3, 25} {3, 5, 50} {2, 5, 15} GIVEN: The greatest common divisor of any two numbers, among the three integers, is 1 The only set that meets this condition is {2, 3, 25} SUM = 2 + 3 + ...”
June 12, 2019
Brent@GMATPrepNow posted a reply to David drove to work at an average (arithmetic mean) speed of in the Problem Solving forum
“Let''s start with a "word equation" We can write: (David''s travel time TO work) + (David''s travel time FROM work) = 2 hours time = distance/speed Let d = the distance each way We can write: d/45 + d/60 = 2 To eliminate the fractions, multiply both sides by 180, the LCM of 45 ...”
June 12, 2019
Brent@GMATPrepNow posted a reply to If x and y are positive integers, are x and y consecutive? in the Data Sufficiency forum
“ Given: x and y are positive integers Target question: Are x and y consecutive? Statement 1: x+y=3 Since x+y=3 are x positive integers, we know that one number must be 1 and the other number must be 2. The answer to the target question is YES, x and y ARE consecutive Since we can ...”
June 12, 2019
Max@Math Revolution posted a new topic called It is known that (1.1)^{17} is approximately equal to 5.05. in the Problem Solving forum
“[GMAT math practice question] It is known that (1.1)^{17} is approximately equal to 5.05. What is the approximate value of (1.1)^{50}? A. 20 B. 40 C. 80 D. 120 E. 160”
June 12, 2019
Max@Math Revolution posted a reply to A 30-60-90 triangle is drawn on the exterior of equilateral in the Problem Solving forum
“=> Since the triangle BCD is a 30-60-90 triangle, CD:BC:BD = 1 : 2 : √3. So, BC = 4, AB = 4, and BD = 2 √3. Angle ABD is a right angle since angle ABC is 60 degrees, and angle CBD is 30 degrees. By Pythagoras’ theorem, AD^2 = AB^2 + BD^2 = 16 + 12 = 28. Therefore, AD = 2√7. ...”
June 12, 2019
Max@Math Revolution posted a new topic called If x and y are positive integers, are x and y consecutive? in the Data Sufficiency forum
“[GMAT math practice question] If x and y are positive integers, are x and y consecutive? 1) x+y=3 2) xy=2”
June 12, 2019
Max@Math Revolution posted a reply to 0 < a < b < c. Is a < 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 ...”
June 12, 2019
ceilidh.erickson posted a reply to Since the routine use of antibiotics can give rise to resist in the Critical Reasoning forum
“If we want to STRENGTHEN an argument, we must first determine how the argument is currently logically flawed, i.e. what information it''s missing. Premises: The routine use of antibiotics can give rise to resistant bacteria capable of surviving antibiotic environments Explanation 1: The ...”
June 11, 2019
ceilidh.erickson posted a reply to If a is an integer, what is the units digit of a^18? in the Data Sufficiency forum
“For more on finding patterns in units digits, see here: https://www.beatthegmat.com/what-is-the-unit-digit-of-the-sum-t297452.html#800962 http://www.beatthegmat.com/remainder-t289535.html#767961 http://www.beatthegmat.com/if-r-s-and-t-are-all-positive-integers-t17201.html#548713 ...”
June 11, 2019
ceilidh.erickson posted a reply to If a is an integer, what is the units digit of a^18? in the Data Sufficiency forum
“When dealing with UNITS DIGITS and exponents, we must look for a pattern. If $$a$$ is an integer, what is the units digit of $$a^{18}?$$ (1) $$a^2$$ has a units digit of 9. We can express $$a^{18}$$ as $$(a^2)^9$$ . If $$a^2$$ has a units digit of $$9$$, then $$a^{18}$$ will have the same ...”
June 11, 2019
ceilidh.erickson posted a reply to In the figure above, what fraction of the circle with center in the Problem Solving forum
“Angles opposite one another have the same measurement. Thus, both non-shaded regions measure 45 degrees from the center of the circle, for a total of 90 degrees. A circle is 360 degrees, so 90 degrees is 1/4 of the circle that is unshaded. That leaves 3/4 of the circle shaded. The answer is D.”
June 11, 2019
ceilidh.erickson posted a reply to Especially in the early years, new entrepreneurs may need to in the Sentence Correction forum
“This question is testing PRONOUN AGREEMENT, PARALLELISM, and IDIOMS. Especially in the early years, new entrepreneurs may need to find resourceful ways, like renting temporary office space or using answering services, that make their company seem large and more firmly established than they may ...”
June 11, 2019
ceilidh.erickson posted a reply to Lyme disease is caused by a bacterium transmitted to humans in the Critical Reasoning forum
“The NUMBER v. PROPORTION flaw is a very common type of logical flaw on CR. For more examples, see: https://www.beatthegmat.com/critical-reasoning-og-13-t277764.html#725229 http://www.beatthegmat.com/i-m-doubting-the-official-answer-of-a-cr-question-t156084.html#551227 ...”
June 11, 2019
ceilidh.erickson posted a reply to Lyme disease is caused by a bacterium transmitted to humans in the Critical Reasoning forum
“With CR questions, pay particular attention to any arguments that involve the conflation of NUMBERS and PROPORTIONS. Premises: - deer ticks pick up the bacterium while in the larval stage by feeding on infected white-footed mice - certain other species on which the larvae feed do not harbor ...”
June 11, 2019
ceilidh.erickson posted a reply to How to Improve Score Beyond V32 in the GMAT Verbal & Essays forum
“Whenever students tell me "I''ve been studying for months but I haven''t seen any improvement!" usually the missing factor turns out to be that they haven''t been REVIEWING deeply. You mention "completing" the OG, but you don''t tell us anything else about your study process. ...”
June 11, 2019
Brent@GMATPrepNow posted a reply to How many integers between in the Problem Solving forum
“We want to determine how many integers end in 13 For example, 324713, 324813, 324913, 325013, . . . etc. Recognize that, for every 100 consecutive integers, only 1 will end in 13. There are 133,900 integers between 324,700 and 458,600 (since 458,600 - 324,700 = 133,900) Of those 133,900 ...”
June 11, 2019
Brent@GMATPrepNow posted a reply to sum of these 24 integers? in the Problem Solving forum
“Since we''re adding 24 numbers, we know that: Six numbers will be in the form 1--- Six numbers will be in the form 2--- Six numbers will be in the form 3--- Six numbers will be in the form 4--- Let''s first see what the sum is when we say all 24 numbers are 1000, 2000, 3000 or 4000 The sum = ...”
June 11, 2019
June 11, 2019
Brent@GMATPrepNow posted a reply to A certain library 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” June 11, 2019 Brent@GMATPrepNow posted a reply to rates 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, ...” June 11, 2019 Brent@GMATPrepNow posted a reply to DS in the Data Sufficiency forum “Target question: Is b (the y-coordinate of the point on the line) positive? Given: Line k passes through the origin and through the point (a,b) Statement 1: The slope of line k is negative There are several lines and points that satisfy statement 1. Here are two: Case a: ...” June 11, 2019 Brent@GMATPrepNow posted a reply to In a certain pond in the Problem Solving forum “We can use equivalent ratios here. We''re told that the proportion of tagged fish in the 50-fish SAMPLE is equal to the the proportion of tagged fish in the ENTIRE pond. So, (# tagged fish in SAMPLE)/50 = (total # tagged fish)/(total # of fish in POND) Let x = # of fish in the entire ...” June 11, 2019 Max@Math Revolution posted a new topic called The quadrilateral ABCD is a kite. If AB = BC = 20, CD = DA = in the Problem Solving forum “https://i.postimg.cc/YvpLPr9z/6-11.png A. 60 B. 72 C. 84 D. 96 E. 108” June 11, 2019 Max@Math Revolution posted a new topic called Is x^3-x^2+x-1 > 0? in the Data Sufficiency forum “[GMAT math practice question] Is x^3-x^2+x-1 > 0? 1) x^5 > x^2 2) x^3 + x > x^2 + 1” June 11, 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. ...” June 11, 2019 Brent@GMATPrepNow posted a reply to In the multiplication above, # represents a single digit. in the Problem Solving forum “We''re told that # times 512 equals two thousand and something. Well, 4 times 512 = two thousand and something. And 5 times 512 = two thousand and something. No other digits, when multiplied by 512 will give us two thousand and something So, let''s test 4 and 5 (answer choices C and D) If ...” June 10, 2019 Brent@GMATPrepNow posted a reply to In the xy-plane shown, is the slope of the line L negative ? in the Data Sufficiency forum “Target question: Is the slope of the line L negative ? After scanning the two statement, I see that we can jump straight to . . . Statements 1 and 2 combined The COMBINED statements tell us that line l passes through quadrants III and IV. There are several lines that satisfy BOTH ...” June 10, 2019 Brent@GMATPrepNow posted a reply to If x ≠ −2, then 5x+10x+2=5x+10x+2 in the Problem Solving forum “Approach #2: We''re asked to evaluate (find the value of) the given expression. Since all of the answer choices are constants (just numbers), we know that the given expression must evaluate to be ONE of the answer choices FOR ALL VALUES OF X. So, let''s test a value of x Try x = 1 We get: ...” June 10, 2019 Brent@GMATPrepNow posted a reply to If x ≠ −2, then 5x+10x+2=5x+10x+2 in the Problem Solving forum “(5x+10)/(x+2) = (5(x+2))/(x+2) = 5 Answer: D Cheers, Brent” June 10, 2019 Brent@GMATPrepNow posted a reply to For any integers a and b, min(a, b) and max(a, b) denote in the Data Sufficiency forum “Notice that min(3, 4) = 3 Notice that min(2, 2) = 2 Notice that min(1, 11) = 1 KEY PROPERTY: In general, we can say that, if min(a,b) = c, then we know that c ≤ a and c ≤ b Target question: What is max(y, 8)? Statement 1: min(9, x) = y This tells us that y ≤ 9 Let''s test ...” June 10, 2019 Brent@GMATPrepNow posted a reply to From a group of 10 students, 7 girls and 3 boys, a teacher in the Problem Solving forum “Take the task of arranging students and break it into stages. Stage 1: Select two girls Since the order in which we select the women does not matter, we can use combinations. We can select 2 girls from 7 girls in 11C2 ways (21 ways) So, we can complete stage 1 in 21 ways If anyone is ...” June 10, 2019 Max@Math Revolution posted a new topic called A 30-60-90 triangle is drawn on the exterior of equilateral in the Problem Solving forum “https://i.postimg.cc/hXcChgYX/6-10.png A. 3 B. 4 C. 5 D. √7 E. 2√7” June 10, 2019 Max@Math Revolution posted a new topic called 0 < a < b < c. Is a < 3? in the Data Sufficiency forum “[GMAT math practice question] 0 < a < b < c. Is a < 3? 1) 1/c > 1/3 2) 1/a + 1/b + 1/c = 1” June 10, 2019 Max@Math Revolution posted a reply to If 0.001 < a < 0.002 and 1,000 < b < 2,000, whic in the Problem Solving forum “=> $$\frac{a^3b^2+a^2b^3}{a^3b^3}=\frac{1}{a}+\frac{1}{b}$$ Since 0.001 < a < 0.002 and 1,000 < b < 2,000, we have 500 < 1/a < 1000 and 1/2000 < 1/b < 1/1000. Thus $$500+\frac{1}{2000}\ <\ \frac{a^3b^2+a^2b^3}{a^3b^3}\ <\ 1000+\frac{1\ }{1000}$$ ...” June 10, 2019 Max@Math Revolution posted a reply to he sequence An satisfies An = An-1An-2, where n is a positiv in the Problem Solving forum “=> A1 = 1 A2 = 2 A3 = A2/A1 = 2/1 =2 A4 = A3/A2 = 2/2 =1 A5 = A4/A3 = 1/2 A6 = A5/A4 = (1/2)/1 = 1/2 A7 = A6/A5 = (1/2)/(1/2) =1 A8 = A7/A8 = 1/(1/2) = 2 Since A7 = 1 and A8 = 2, the sequence is periodic with period 6. Thus, A123 = A3 = 2 since 123=6·20+3 Therefore, the answer is ...” June 10, 2019 Max@Math Revolution posted a reply to If the symbol # represents one of addition, subtraction, mul 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 ...” June 10, 2019 Max@Math Revolution posted a reply to We define ‘a mod n’ to be the remainder when a is divid 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 ...” June 10, 2019 Brent@GMATPrepNow posted a reply to If 3 different integers are randomly selected from the integ in the Problem Solving forum “I specifically created this question to illustrate the importance of calculating the denominator first (when using counting techniques to solve a probability question) There are two reasons why you should calculate the denominator first: 1) The denominator is almost always easier to calculate ...” June 7, 2019 Max@Math Revolution posted a new topic called If 0.001 < a < 0.002 and 1,000 < b < 2,000, which of the fo in the Problem Solving forum “[GMAT math practice question] 6.7 If 0.001 < a < 0.002 and 1,000 < b < 2,000, which of the following could be the value of a^3b^2+a^2b^3/a^3b^3? A. 15 B. 125 C. 625 D. 1250 E. 6250” June 7, 2019 Max@Math Revolution posted a reply to If 272/4^6 = 1/4^m+ 1/4^n, what is the value of mn? in the Problem Solving forum “=> $$\frac{272}{4^6}=\frac{17}{4^4}=\frac{1+16}{4^4}=\frac{1}{4^4}+\frac{16}{4^4}=\frac{1}{4^4}+\frac{1}{4^2}$$ Thus m = 4 and n = 2, or m = 2 and n = 4. So, mn = 8. Therefore, the answer is D. Answer: D ” June 7, 2019 Max@Math Revolution posted a new topic called If the symbol # represents one of addition, subtraction, mul in the Data Sufficiency forum “[GMAT math practice question] If the symbol # represents one of addition, subtraction, multiplication, or division, what is the value of (2 # 1)? 1) 2 # 2 = 1 2) (–1/2) # (-1) = 1/2” June 7, 2019 Max@Math Revolution posted a reply to Is x < y < z ? 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 ...” June 7, 2019 Max@Math Revolution posted a new topic called he sequence An satisfies An = An-1An-2, where n is a positiv in the Problem Solving forum “n satisfies An = An-1/An-2, where n is a positive integer greater than 2. If A1=1 and A2=2, then A123=? A. 1/2 B. 1/4 C. 1 D. 2 E. 4” June 7, 2019 Max@Math Revolution posted a reply to 1 + 2 + … + k = k(k+1)/2. m and n are positive integers sa in the Problem Solving forum “=> n + (n+1) + … + (m-1) + m = 1 + 2 + … + (n-1) + n + (n+1) + … + (m-1) + m – (1 + 2 + … + (n-1)) = m(m+1)/2 - (n-1)(n-1+1)/2 = m(m+1)/2 – n(n-1)/2 = (1/2)(m(m+1) – n(n-1)) = (1/2)(m^2 + m – n^2 + n) = (1/2)(m^2 – n^2 + m + n ) = (1/2)( (m+n)(m-n) + (m+n) ) = ...” June 7, 2019 Max@Math Revolution posted a new topic called We define ‘a mod n’ to be the remainder when a is divided b in the Data Sufficiency forum “[GMAT math practice question] We define ‘a mod n’ to be the remainder when a is divided by n. What is the value of ‘a mod 12’? 1) a mod 3=1 2) a mod 4=a mod 2” June 7, 2019 Max@Math Revolution posted a reply to If two integers have no common factors other than 1, they ar 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 ...” June 7, 2019 Brent@GMATPrepNow posted a reply to Puzzling probability question in the Problem Solving forum “P(selecting a sibling pair) = P(select a business student with a sibling AND select a law student who is that business student''s sibling) = P(select a business student with a sibling) x P(select a law student who is that business student''s sibling) = 30/500 x 1/800 = 30/400,000 = 3/40,000 = ...” June 6, 2019 Brent@GMATPrepNow posted a new topic called If 3 different integers are randomly selected from the integ in the Problem Solving forum “If 3 different integers are randomly selected from the integers from 1 to 12 inclusive, what is the probability that a triangle can be constructed so that its 3 sides are the lengths of the 3 selected numbers? A) 3/8 B) 7/18 C) 19/44 D) 39/88 E) 11/24 Answer: C Source: ...” June 6, 2019 Brent@GMATPrepNow posted a reply to GMAT Prep in the Problem Solving forum “In the 4 months leading up to March, the company PRODUCES 4x rakes (4 months at x/month = 4x) On March 1, x/2 rakes are SHIPPED, leaving 3.5x rakes for which the company must pay storage fees. On April 1, x/2 rakes are SHIPPED, leaving 3x rakes for which the company must pay storage fees. ...” June 5, 2019 Brent@GMATPrepNow posted a reply to VIC question -- picking numbers in the Problem Solving forum “Originally, T people were to pay total cost of x dollars. So, each person pays x/T each. After S people drop out, there are T-S people to pay total cost of x dollars. So, each person pays x/(T-S) each. The additional amount that each must pay = New cost per person - original cost per ...” June 5, 2019 Brent@GMATPrepNow posted a reply to Hotel California in the Problem Solving forum “One option is to use the Double Matrix method. Here, we have a population of lightbulbs, and the two characteristics of each bulb are: - incandescent or fluorescent - on or off Since the questions asks us to find a certain PERCENT, let''s say that there are 100 bulbs altogether. So, we ...” June 5, 2019 Brent@GMATPrepNow posted a reply to Of the 12 temporary employees in a certain company, 4 will in the Problem Solving forum “Take the task of selecting the employees and break it into stages. Stage 1: Select the 3 women The order in which we select the women does not matter, so we can use combinations. We can select 3 women from 5 women in 5C3 ways (= 10 ways) Aside: If anyone is interested, here''s video on ...” June 5, 2019 Brent@GMATPrepNow posted a reply to If k is 96% greater than its reciprocal, which of the follow in the Problem Solving forum “k is 96% greater than its reciprocal The reciprocal of k is 1/k So, we can write: k = (1/k) + (96% of 1/k) In other words: k = (1/k) + 0.96(1/k) Simplify: k = 1.96(1/k) Simplify: k = 1.96/k Multiply both sides by k to get: k² = 1.96 Solve: k = 1.4 of k = -1.4 Rewrite as follows: k = 7/5 of ...” June 5, 2019 Max@Math Revolution posted a new topic called If 272/4^6 = 1/4^m+ 1/4^n, what is the value of mn? in the Problem Solving forum “[GMAT math practice question] If 272/4^6 = 1/4^m+ 1/4^n, what is the value of mn? A. 2 B. 4 C. 6 D. 8 E. 12” June 5, 2019 Max@Math Revolution posted a reply to In the sequence An, A1=1，A2=2, and An+2=An+1+An+An-1+….+ in the Problem Solving forum “=> A3 = A1 + A2 A4 = A1 + A2 + A3 = A3 + A3 = 2A3 A5 = A1 + A2 + A3 + A4 = A4 + A4 = 2A4 … A13 = A1 + A2 + A3 + … + A11 + A12 = A12 + A12 = 2A12 A14 = A1 + A2 + A3 + … + A12 + A13 = A13 + A13 = 2A13 = 2(2A12) = 4A12 Thus A14 / A12 = 4 Therefore, E is the answer. Answer: E” June 5, 2019 Max@Math Revolution posted a new topic called Is x < y < z ? in the Data Sufficiency forum “[GMAT math practice question] Is x < y < z ? 1) |x+2| < y < z+2 2) |x-2| < y < z-2” June 5, 2019 Max@Math Revolution posted a reply to Is pqr is a multiple of 5? 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 ...” June 5, 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. ...” June 5, 2019 Brent@GMATPrepNow posted a new topic called If k is 96% greater than its reciprocal, which of the follow in the Problem Solving forum “If k is 96% greater than its reciprocal, which of the following is an integer? A) 3k/7 B) 3k/5 C) 5k/7 D) 5k/3 E) 7k/5 Source: www.gmatprepnow.com Difficulty level: 600-650 Answer: C” June 4, 2019 Max@Math Revolution posted a new topic called 1 + 2 + … + k = k(k+1)/2. m and n are positive integers sati in the Problem Solving forum “[GMAT math practice question] 1 + 2 + … + k = k(k+1)/2. m and n are positive integers satisfying n < m. What is the value of n + (n+1) + … + (m-1) + m? A. (m+n)(m-n-1)/2 B. (m+n)(m-n+1)/2 C. (m-n)(m+n-1)/2 D. (m-n)(m+n+1)/2 E. (m+n)(m-n-1)/4” June 4, 2019 Max@Math Revolution posted a new topic called If two integers have no common factors other than 1, they ar in the Data Sufficiency forum “[GMAT math practice question] If two integers have no common factors other than 1, they are called relatively prime. Are x and z relatively prime? 1) x and y are relatively prime. 2) y and z are relatively prime.” June 4, 2019 Brent@GMATPrepNow posted a reply to Which of the following sets contains only factors of 45? in the Problem Solving forum “Scan the answer choices....(C and D)..... 13 is NOT a factor of 45. ELIMINATE C By the process of elimination, the correct answer is D Cheers, Brent Scan the two remaining answer choices.... 7 is NOT a factor of 45. ELIMINATE A, B and E” June 3, 2019 Brent@GMATPrepNow posted a reply to A company has two types of machines, type R and type S. in the Problem Solving forum “Here''s another approach . . . When it comes to questions where we must complete an entire job, I often (not always) like to know what can be accomplished in 1 unit of time (in this case, 1 hour). Machine R can complete 1/36 of the job in 1 hour. Machine S can complete 1/18 of the job in 1 ...” June 3, 2019 Brent@GMATPrepNow posted a reply to A company has two types of machines, type R and type S. in the Problem Solving forum “One approach is to assign a "nice" value to the job. Say, the job is to make 36 widgets. R does a certain job in 36 hours This means that machine R''s rate is 1 widget/hour S does the job in 18 hours This means that machine S''s rate is 2 widgets/hour So, their combined rate ...” June 3, 2019 Brent@GMATPrepNow posted a reply to If k^2 = m^2, which of the following must be true? in the Problem Solving forum “The question asks us what MUST be true. So, if we can find a case where a statement is not true, we can eliminate that answer choice. So, for example, one solution to the equation (k² = m²) is k = 1 and m = 1 Now let''s check the answer choices. A. k = m. Test: 1 = 1. Works. Keep A. B. ...” June 3, 2019 Max@Math Revolution posted a new topic called In the sequence An, A1=1，A2=2, and An+2=An+1+An+An-1+….+A2+A in the Problem Solving forum “1=1，A2=2, and An+2=An+1+An+An-1+….+A2+A1. What is the value of A14 / A12? A. 1/4 B. 1/2 C. 1 D. 2 E. 4” June 3, 2019 Max@Math Revolution posted a new topic called Is pqr is a multiple of 5? in the Data Sufficiency forum “[GMAT math practice question] Is pqr is a multiple of 5? 1) p, q and r are consecutive odd integers. 2) p, q and r are prime numbers.” June 3, 2019 Max@Math Revolution posted a reply to m and n are integers. Which of the following cannot be the v in the Problem Solving forum “=> D is likely to be the answer as it is the only one which is divisible by 3. We test (m^2+1)(n^2+1) for divisibility by 3. Note that every integer m can be written as 3k, 3k+1 or 3k+2 for some integer k. If m = 3k, then m^2 = 9k^2, and m^2 + 1 = 9k^2 + 1 = 3(3k^2) + 1. If m = 3k+1, then ...” June 3, 2019 Max@Math Revolution posted a reply to abcd ≠ 0, a:b:c = 2:3:4, c:d = 5:6, and a + b + c – d = in the Problem Solving forum “=> We combine the ratios to form a single ratio for a:b:c:d as follows: a : b : c = 2 : 3 : 4 c : d = 5 : 6 Multiplying both equations by 5 yields a : b : c = 10 : 15 : 20 c : d = 20 : 24 and combining them to form a single ratio gives a : b : c : d = 10 : 15 : 20 : 24 ...” June 3, 2019 Max@Math Revolution posted a reply to x, y and y are positive numbers satisfying x < y < z. 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 ...” June 3, 2019 Max@Math Revolution posted a reply to a, b and c are numbers such that abc ≠ 0 and a/b = b/c=c/d 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 ...” June 3, 2019 Brent@GMATPrepNow posted a reply to A company that ships boxes to a total of 12 distribution in the Problem Solving forum “We need to be able to create AT LEAST 12 codes (to represent the 12 countries). Let''s test the options. Can we get 12 or more color codes with 4 colors? Let''s see . . . 1-color codes = 4 (since there are 4 colors) 2-color codes = We need to choose 2 colors from 4. This can be ...” June 2, 2019 ceilidh.erickson posted a reply to A company that ships boxes to a total of 12 distribution in the Problem Solving forum “On problems like this, the easiest solution is just to use the answer choices and count the possibilities. Imagine these options for colors: R = red O = orange Y = yellow G = green B = blue P = purple (we''ll add more if we need them) For each answer choice, count the options for a single ...” June 2, 2019 ceilidh.erickson posted a reply to If $$a, b$$, and $$c$$ are integers, what is the value of in the Data Sufficiency forum “Ian has an excellent point here! The question doesn''t specify non-negative. I think this shows how we all really synthesize before we extrapolate - after reading statement 1, when I read statement 2 I immediately thought "well a=5, but I don''t know that from this one alone" and didn''t ...” June 2, 2019 ceilidh.erickson posted a reply to Mike has twice as many stamps as Jean has. After he gives in the Problem Solving forum “This type of 2-variable word problem is know as an EXCHANGE problem, and it can be tricky. For more on exchange problems and translating other tricky word problems, here is a video lesson: https://www.youtube.com/watch?v=5Kg6mjNhLM8&list=PLYZACiD6j3VsFlDR68gbF9CK9gZedcPbY&index=11&t=0s ...” June 1, 2019 ceilidh.erickson posted a reply to Mike has twice as many stamps as Jean has. After he gives in the Problem Solving forum “We can easily translate this algebraically. Let M = Mike''s original # of stamps, and J - Jean''s original # of stamps. Mike has twice as many stamps as Jean has --> $$M=2J$$ After he gives Jean 6 stamps, he still has 8 more stamps than Jean does --> $$M-6=(J+6)+8$$ *NB: remember that ...” June 1, 2019 ceilidh.erickson posted a reply to If $$a, b$$, and $$c$$ are integers, what is the value of in the Data Sufficiency forum “If $$a, b$$, and $$c$$ are integers, what is the value of $$a$$? We''re given no information in the question stem except that these variables are integers. So, we have to dive into the statements: (1) $$2^a+2^b=33$$ Think of combinations of powers of 2 that would add to 33. Since 33 is odd, ...” June 1, 2019 ceilidh.erickson posted a reply to GMAT Official Practice Tes #6 in the GMAT Math forum “Since we''re asked what the value is *closest* to, Marty is right - we don''t have to do complicated math, we can just estimate with the larger numbers. But, for a lot of exponent questions with addition or subtraction, we can''t simply add or subtract the bases, but we can FACTOR: ...” June 1, 2019 ceilidh.erickson posted a reply to A fair coin has 2 distinct flat sides—one of which bears t in the GMAT Integrated Reasoning forum “If one coin flip has a 1/2 chance of landing face up, then the probability that two coin flips will both be face up is $$\frac{1}{2}\cdot\frac{1}{2}=\frac{1}{4}$$ Thus, for any M coin flips, the probability of all flips landing face up is $$p=\frac{1}{2^M}$$ , and for any N coin flips, the ...” June 1, 2019 ceilidh.erickson posted a reply to Need help regarding how to handle SC and RC questions in the GMAT Verbal & Essays forum “GMAT verbal can be very difficult if English isn''t your native language, so I commend you for putting the work in. The good news is that there are recognizable patterns that the GMAT uses again and again, especially in SC. Here''s some advice on how to be more ''mathematical'' about verbal: ...” June 1, 2019 Brent@GMATPrepNow posted a reply to What is the total cost to make 7 long distance telephone in the Data Sufficiency forum “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: Case a: Each call was 2 minutes long, for a total of 14 minutes. At$0.32 per ...”
June 1, 2019
Brent@GMATPrepNow posted a reply to Of the 60 animals on a certain farm, $$\frac{2}{3}$$ are in the Data Sufficiency forum
“Target question: How many of the animals are cows? Given: Of the 60 animals in a certain farm, 2/3 are either pigs or cows Let P = # of pigs Let C = # of cows 2/3 of 60 = 40, so we can say that P + C = 40 Statement 1: The farm has MORE THAN twice as many cows as it has pigs. In other ...”
May 31, 2019
Max@Math Revolution posted a new topic called m and n are integers. Which of the following cannot be the v in the Problem Solving forum
“[GMAT math practice question] m and n are integers. Which of the following cannot be the value of (m^2+1)(n^2+1)? A. 10 B. 20 C. 50 D. 60 E. 100”
May 31, 2019
Max@Math Revolution posted a reply to m and n are positive numbers. (2^m)^n = 512. What is the min in the Problem Solving forum
“=> (2^m)^n = 2^{mn} = 512 = 2^9. Thus mn = 9. Recall that if mn is a fixed constant, and m and n are positive numbers, then m + n has its minimum value when m = n. Thus, we must have m = n = 3 to obtain the minimum value of m + n = 3 + 3 = 6. Therefore, the answer is D. Answer: D”
May 31, 2019
Max@Math Revolution posted a new topic called x, y and y are positive numbers satisfying x < y < z. Is x < in the Data Sufficiency forum
“[GMAT math practice question] x, y and y are positive numbers satisfying x < y < z. Is x < 5? 1) x^2 + y^2 + z^2 = 125 2) y^2 = 25”
May 31, 2019
Max@Math Revolution posted a reply to x = -1. What is the value of x + x^n + x^{n+1} + x^{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. Since we ...”
May 31, 2019
Max@Math Revolution posted a new topic called abcd ≠ 0, a:b:c = 2:3:4, c:d = 5:6, and a + b + c – d = 42. in the Problem Solving forum
“[GMAT math practice question] abcd ≠ 0, a:b:c = 2:3:4, c:d = 5:6, and a + b + c – d = 42. What is the value of d? A. 6 B. 12 C. 24 D. 36 E. 48”
May 30, 2019
Max@Math Revolution posted a reply to x + 2y + 3z = 4 and 5x + 4y + 3z = 8. What is the value of x in the Problem Solving forum
“=> When we add the two equations, we obtain (x+2y+3z) + (5x+4y+3z) = 6(x+y+z) = 4 + 8 = 12. Dividing both sides of this equation by 6 yields x+y+z = 2. Therefore, the answer is B. Answer: B”
May 30, 2019
Max@Math Revolution posted a new topic called a, b and c are numbers such that abc ≠ 0 and a/b = b/c=c/d. in the Data Sufficiency forum
“[GMAT math practice question] a, b and c are numbers such that abc ≠ 0 and a/b = b/c=c/d. What is the value of a/d? 1) a = 1 2) b = 2”
May 30, 2019
Max@Math Revolution posted a reply to f(x) = anx^n + an-1x^{n-1} + … + a1x + a0. What is the sum 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 ...”
May 30, 2019
Brent@GMATPrepNow posted a reply to A computer programmer needs to print 148 documents. The in the Problem Solving forum
“We can also answer this question using a step-by-step approach based on number sense. IMPORTANT: The word approximately typically suggests that we can be somewhat aggressive with our estimation There are 148 documents and the documents have an average length of 10 pages So, the TOTAL number ...”
May 29, 2019
Max@Math Revolution posted a new topic called m and n are positive numbers. (2^m)^n = 512. What is the min in the Problem Solving forum
“[GMAT math practice question] m and n are positive numbers. (2^m)^n = 512. What is the minimum value of m + n? A. 3 B. 4 C. 5 D. 6 E. 8”
May 29, 2019
Max@Math Revolution posted a reply to When -1/2 < h < 0, which of the following has the grea in the Problem Solving forum
“=> Test each expression by plugging in h = -1/4. h^2-2h+1 = (h-1)^2 = (-(5/4))^2 = 25/16 h^2+h = h(h+1) = -(1/4)(3/4) = -(3/16) h = -1/4 h^2 = (-(1/4))^2 = 1/16 h^3 = (-(1/4))^3 = -(1/64) Therefore, A is the answer. Answer: A”
May 29, 2019
Max@Math Revolution posted a new topic called x = -1. What is the value of x + x^n + x^{n+1} + x^{n+2}? in the Data Sufficiency forum
“[GMAT math practice question] x = -1. What is the value of x + x^n + x^{n+1} + x^{n+2}? 1) n is a prime number 2) n is an odd number”
May 29, 2019
Max@Math Revolution posted a reply to What is the value of 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 ...”
May 29, 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. ...”
May 29, 2019
Brent@GMATPrepNow posted a reply to x + 2y + 3z = 4 and 5x + 4y + 3z = 8. What is the value of x in the Problem Solving forum
“GIVEN: x + 2y + 3z = 4 5x + 4y + 3z = 8 ADD the two equations to get: 6x + 6y + 6z = 12 Factor: 6(x + y + z) = 12 Divide both sides by 6 to get: x + y + z = 2 Answer: B Cheers, Brent”
May 28, 2019
Brent@GMATPrepNow posted a reply to Two different primes may be said to"rhyme" around in the Problem Solving forum
“If two numbers are rhyming primes, then the integer the rhyme around will be the AVERAGE of the two primes. For example, 3 and 7 rhyme around 5. Notice that the AVERAGE of 3 and 7 is 5. Likewise, 5 and 23 rhyme around 14, and the AVERAGE of 5 and 23 is 14. Now onto the solution... List ...”
May 28, 2019
Brent@GMATPrepNow posted a reply to A certain fruit stand sold apples for $0.70 each and bananas in the Problem Solving forum “Here''s an approach where we test the POSSIBLE SCENARIOS. FACT #1: (total cost of apples) + (total cost of bananas) = 630 CENTS FACT #2: total cost of bananas is DIVISIBLE by 50, since each banana costs 50 cents. Now let''s start testing POSSIBLE scenarios. Customer buys 1 apple. 1 ...” May 28, 2019 Brent@GMATPrepNow posted a reply to From a group of 5 managers (Joo, Kendra, Lee, Marnie, and in the Problem Solving forum “Our goal is to find P(M and N both selected) There are two ways to approach this. Method #1: P(M and N both selected) = P(one of them is selected 1st AND the other selected 2nd) = P(one of them is selected 1st) x P(the other selected 2nd) = (2/5)(1/4) = 1/10 = 0.1 Aside: P(one of them ...” May 28, 2019 Max@Math Revolution posted a new topic called x + 2y + 3z = 4 and 5x + 4y + 3z = 8. What is the value of x in the Problem Solving forum “[GMAT math practice question] x + 2y + 3z = 4 and 5x + 4y + 3z = 8. What is the value of x + y + z? A. 1 B. 2 C. 3 D. 4 E. 5” May 28, 2019 Max@Math Revolution posted a new topic called f(x) = anx^n + an-1x^{n-1} + … + a1x + a0. What is the sum o in the Data Sufficiency forum “nx^n + an-1x^{n-1} + … + a1x + a0. What is the sum of the coefficients of the function f? 1) f(1) = 20 2) f(-1) = 10” May 28, 2019 Brent@GMATPrepNow posted a reply to Car X is 40 miles west of Car Y. Both cars are traveling in the Problem Solving forum “Let''s let Car X''s original position be the initial starting point. So, when Car X is at the initial starting point, Car Y has already traveled 40 miles. My word equation involves the conditions when Car X catches up to Car Y. At that point, we can say: Car X''s TOTAL distance traveled = ...” May 27, 2019 Max@Math Revolution posted a new topic called When -1/2 < h < 0, which of the following has the greatest v in the Problem Solving forum “[GMAT math practice question] When -1/2 < h < 0, which of the following has the greatest value? A. h^2-2h+1 B. h^2+h C. h D. h^2 E. h^3” May 27, 2019 Max@Math Revolution posted a new topic called What is the value of xy? in the Data Sufficiency forum “[GMAT math practice question] What is the value of xy? 1) x^2-4xy+5y^2-4xy+4 = 0 2) |x-4| = - √(y-2)” May 27, 2019 Max@Math Revolution posted a reply to A rectangular board measuring 9 inches by 11 inches is to be in the Problem Solving forum “=> https://i.postimg.cc/hQv3xGTn/5-24.png The smallest number of tiles will be obtained by using as many 2 inch by 3 inch rectangular tiles as possible since they are the larger tiles. As shown in the diagram above, 16 such tiles can be placed on the board, leaving three square inches to ...” May 27, 2019 Max@Math Revolution posted a reply to 6/√5-√5/5=? in the Problem Solving forum “=> $$\frac{6}{\sqrt{5}}-\frac{\sqrt{5}}{5}=\frac{6\sqrt{5}}{\sqrt{5}\sqrt{5}}-\frac{\sqrt{5}}{5}=\frac{6\sqrt{5}}{5}-\frac{\sqrt{5}}{5}=\frac{5\sqrt{5}}{5}=\sqrt{5}$$ Therefore, the answer is C. Answer: C” May 27, 2019 Max@Math Revolution posted a reply to If the average (arithmetic mean) of 5 numbers is 21, what is 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 ...” May 27, 2019 Max@Math Revolution posted a reply to x is a positive number. Is 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. Since we ...” May 27, 2019 Brent@GMATPrepNow posted a reply to Gita is 12 years older than Harvey. In 4 years, Gita will be in the Problem Solving forum “Gita is 12 years older than Harvey. Let x = Harvey''s PRESENT age Let x + 12 = Gita''s PRESENT age In 4 years, . . . . x + 4 = Harvey''s age IN FOUR YEARS (x + 12) + 4 = Gita''s age IN FOUR YEARS . . . Gita will be twice as old as Harvey. So: (Gita''s age IN 4 YEARS) = 2(Harvey''s ...” May 26, 2019 ceilidh.erickson posted a reply to When Congress reconvenes, some newly elected members from in the Sentence Correction forum “This question is testing PARALLELISM and IDIOMS. When Congress reconvenes, some newly elected members from rural states will try and establish tighter restrictions for the amount of grain farmers are to be allowed to grow and to encourage more aggressive sales of United States farm products ...” May 25, 2019 ceilidh.erickson posted a reply to Is $$a > |b|?$$ in the Data Sufficiency forum “For more an ABSOLUTE VALUE with INEQUALITIES, see: https://www.beatthegmat.com/if-x-is-not-equal-to-0-t295221.html#793307 https://www.beatthegmat.com/if-x-y-is-x-y-1-x-0-2-t295200.html#793303 https://www.beatthegmat.com/gmat-prep-1-question-3-t288924.html#765468” May 25, 2019 ceilidh.erickson posted a reply to Is $$a > |b|?$$ in the Data Sufficiency forum “Since this question contains an absolute value, we must be sure to think about NEGATIVE as well as positive possibilities. First, get like bases: $$2^{a-b}>2^4$$ We can infer: $$a-b>4$$ $$a>b+4$$ Since a is greater than b+4, it must also be greater than b itself. But be ...” May 25, 2019 ceilidh.erickson posted a reply to Bob works exactly 8 hours per day assembling widgets at a in the Data Sufficiency forum “If we want to know how many widgets Bob assembles in 4 hours, we need to know his constant RATE of widget assembly. 1) Bob produces 20 widgets in a full workday. We know that a full workday is 8 hours, so this is sufficient to tell us that his rate is 2.5 widgets per hour. Or, you can infer ...” May 25, 2019 ceilidh.erickson posted a reply to Set S consists of five consecutive integers, and set T consi in the Data Sufficiency forum “Set S consists of five consecutive integers, and set T consists of seven consecutive integers. Is the median of the numbers in set S equal to the median of the numbers in set T? Let''s first look at 2 examples of consecutive sets that do have the same median to try to contextualize the ...” May 25, 2019 ceilidh.erickson posted a reply to In Dewey Elementary School, there are two second-grade in the Problem Solving forum “For more on estimating to find right answers on weighted average questions, see: https://www.beatthegmat.com/mixture-problem-og-problem-t295940.html#796297 https://www.beatthegmat.com/mgmat-5th-edition-2-part-question-t267680.html#789804 ...” May 25, 2019 ceilidh.erickson posted a reply to In Dewey Elementary School, there are two second-grade in the Problem Solving forum “Alternatively, you could treat this as a WEIGHTED AVERAGE problem. If one class had 40% walk-to-schoolers and the other had 80%, the weighted average of both classes must be between 40 and 80. Eliminate A. If we had an equal number of students in each class, we''d end up exactly halfway ...” May 25, 2019 ceilidh.erickson posted a reply to In Dewey Elementary School, there are two second-grade in the Problem Solving forum “In Dewey Elementary School, there are two second-grade classes: class A has 35 students and class B has 45 students. If 40% of the students in class A walk to school, and 80% of the students in class B walk to school, what percent of all the students in the second-grade at Dewey Elementary walk to ...” May 25, 2019 ceilidh.erickson posted a reply to Carlos runs a lap around the track in x seconds. His second in the Problem Solving forum “We''re simply looking for the average time per lap (not an average rate or anything more complicated). His lap times in seconds are: 1) x 2) x + 5 3) x - 2 The average of these is: $$\frac{\left(x\right)+\left(x+5\right)+\left(x-2\right)}{3}=\frac{3x+3}{3}=x+1$$ Bear in mind that this is ...” May 25, 2019 Brent@GMATPrepNow posted a reply to Al and Ben are drivers for SD Trucking Company. One snowy da in the Problem Solving forum “Let''s start with a "word equation" (Ben''s travel distance) + (Al''s travel distance) = 240 miles Let t = Al''s travel time (in hours) So, t + 3= Ben''s travel time (since Ben spent 3 more hours driving) Distance = (rate)(time) So, our word equation becomes... (20)(t + 3) = ...” May 24, 2019 Brent@GMATPrepNow posted a reply to What is x in the diagram below? in the Problem Solving forum “The important thing to recognize here is that there are two SIMILAR TRIANGLES hiding in this diagram. http://s24.postimg.cc/50bvp89dt/sim_tri.jpg Notice that these two triangles share both a 90-degree angle AND the angle I''ve denoted with a purple dot. Since the 3 angles in each triangle must ...” May 24, 2019 Max@Math Revolution posted a new topic called A rectangular board measuring 9 inches by 11 inches is to be in the Problem Solving forum “[GMAT math practice question] A rectangular board measuring 9 inches by 11 inches is to be covered with 2 inch by 3 inch rectangular tiles and 1-inch square tiles. What is the smallest number of tiles that can be used to cover the board? A. 19 B. 20 C. 22 ...” May 24, 2019 Max@Math Revolution posted a reply to How many roots does the equation (x^2-1)/(x+1)=x have? in the Problem Solving forum “=> (x^2-1)/(x+1)=x => (x+1)(x-1) / (x+1) = x => x-1 = x by canceling (x+1). But x – 1 = x has no solution. Therefore, the answer is A. Answer: A” May 24, 2019 Max@Math Revolution posted a new topic called If the average (arithmetic mean) of 5 numbers is 21, what is in the Data Sufficiency forum “[GMAT math practice question] If the average (arithmetic mean) of 5 numbers is 21, what is their standard deviation? 1) The least of the 5 numbers is 21 2) The greatest of the 5 numbers is 21” May 24, 2019 Max@Math Revolution posted a reply to If m and n are non-negative integers, what is the value of m 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 ...” May 24, 2019 Brent@GMATPrepNow posted a reply to j, k, m, x, y and z are positive integers. When j is divided in the Problem Solving forum “Useful remainder property: When positive integer N is divided by positive integer D, the remainder R is such that 0 ≤ R < D For example, if we divide some positive integer by 7, the remainder will be 6, 5, 4, 3, 2, 1, or 0 When j is divided by k, the remainder is m The above property ...” May 23, 2019 Max@Math Revolution posted a new topic called 6/√5-√5/5=? in the Problem Solving forum “[GMAT math practice question] $$\frac{6}{\sqrt{5}}-\frac{\sqrt{5}}{5}=?$$ A. 1 B. -1 C. √5 D. -√5 E. 2√5” May 23, 2019 Max@Math Revolution posted a reply to If a=2b=6c for positive integers a, b, and c, which of the f in the Problem Solving forum “=> Since 2b = 6c, we have b = 3c. Thus, abc = (6c)*(3c)*c = 18c^3 and abc is a multiple of 18. This implies that abc is a multiple of both 2 and 9. Of the above answer choices, only 2250 is a multiple of both 2 and 9. Therefore, the answer is C. Answer: C” May 23, 2019 Max@Math Revolution posted a new topic called x is a positive number. Is x > 1? in the Data Sufficiency forum “[GMAT math practice question] x is a positive number. Is x > 1? 1) √x > x 2) x^3 - x < 0” May 23, 2019 Max@Math Revolution posted a reply to If m and n are positive integers, is m/n a terminating decim 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 ...” May 23, 2019 Brent@GMATPrepNow posted a reply to Challenge question: Is positive integer p even? in the Data Sufficiency forum “------ASIDE--------------------- Here''s a useful rule: If the prime factorization of N = (p^a)(q^b)(r^c) . . . (where p, q, r, etc are different prime numbers), then N has a total of (a+1)(b+1)(c+1)(etc) positive divisors. Example: 14000 = (2^4)(5^3)(7^1) So, the number of positive divisors ...” May 22, 2019 Brent@GMATPrepNow posted a new topic called j, k, m, x, y and z are positive integers. When j is divided in the Problem Solving forum “j, k, m, x, y and z are positive integers. When j is divided by k, the remainder is m. When x is divided by y, the remainder is z. If ky = 75, which of the following CANNOT be the value of mz? i) 49 ii) 50 iii) 56 A) iii only B) i and ii C) i and iii D) ii and iii E) i, ii and iii ...” May 22, 2019 Rich.C@EMPOWERgmat.com posted a reply to Three-fourths of the area of a rectangular lawn 30 feet wide in the Problem Solving forum “Hi All, We''re told that 3/4 of the AREA of a rectangular lawn 30 feet wide by 40 feet long is to be enclosed by a rectangular fence. We''re asked if the enclosure has full width and REDUCED length rather than full length and REDUCED width, how much LESS fence will be needed. This question is ...” May 22, 2019 Rich.C@EMPOWERgmat.com posted a reply to In quadrilateral ABCD above, what is the length of AB ? in the Problem Solving forum “Hi All, We''re asked for the length of AB in quadrilateral ABCD. When dealing with ''weird'' shapes, it often helps to break the shape down into ''pieces'' that are easier to deal with. Here, if you draw a line from B to D, you will from 2 RIGHT TRIANGLES. Triangle BCD has legs of 3 and ...” May 22, 2019 Rich.C@EMPOWERgmat.com posted a reply to If rectangle ABCD is inscribed in the circle above, what is in the Problem Solving forum “Hi All, We''re told that a rectangle with sides of 5 and 12 is inscribed in the circle. We''re asked for the area of the circular region. This question is based on a number of math patterns that can help you to save time answering the question. First, any square or rectangle that is inscribed ...” May 22, 2019 Brent@GMATPrepNow posted a reply to If n is an integer greater than 6, which of the following in the Problem Solving forum “One approach is to test values If n = 7, we get: (A) 7(7 + 1)(7 – 4) = (7)(8)(3). Definitely divisible by 3. KEEP (B) 7(7 + 2)(7 – 1) = (7)(9)(6). Definitely divisible by 3. KEEP (C) 7(7 + 3)(7 – 5) = (7)(10)(4). NOT divisible by 3. ELIMINATE. (D) 7(7 + 4)(7 – 2) = (7)(11)(5). NOT ...” May 22, 2019 Max@Math Revolution posted a new topic called How many roots does the equation (x^2-1)/(x+1)=x have? in the Problem Solving forum “[GMAT math practice question] How many roots does the equation (x^2-1)/(x+1)=x have? A. 0 B. 1 C. 2 D. 3 E. 4” May 22, 2019 Max@Math Revolution posted a reply to If f(x)=x^4+4x^2+7, f(x)=g(x)^2+3 and g(x) > 0, then g(x) in the Problem Solving forum “=> g(x)^2 = f(x) – 3 = x^4+4x^2+7 – 3 = x^4+4x^2+4 = (x^2+2)^2 Thus, since g(x) > 0, g(x)=x^2+2. Therefore, B is the answer. Answer: B” May 22, 2019 Max@Math Revolution posted a new topic called If m and n are non-negative integers, what is the value of m in the Data Sufficiency forum “[GMAT math practice question] If m and n are non-negative integers, what is the value of mn? 1) 3^m = 5^n 2) |m| = - √n” May 22, 2019 Max@Math Revolution posted a reply to Is x > 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 ...” May 22, 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. ...” May 22, 2019 Rich.C@EMPOWERgmat.com posted a reply to If R, S, and T are points on a line in the Data Sufficiency forum “Hi All, We''re told that R, S, and T are points on a line, R is 5 meters from T and R is 2 meters from S. We''re asked for the distance between S and T. This question can be solved with a bit of logic and Arithmetic (and you might find it helpful to draw some actual number lines). (1) R is ...” May 21, 2019 Rich.C@EMPOWERgmat.com posted a reply to Is n equal to zero? in the Data Sufficiency forum “Hi All, We''re asked if N is equal to zero. This is a YES/NO question and can be answered with a mix of Number Properties and TESTing VALUES. (1) The PRODUCT of N and some NON-ZERO number is 0 When multiplying any non-zero number by 0, the result will ALWAYS be 0 (for example: 1x0 = 0, ...” May 21, 2019 Rich.C@EMPOWERgmat.com posted a reply to If r and s are positive numbers and θ is one in the Data Sufficiency forum “Hi All, We''re told that R and S are POSITIVE NUMBERS and θ is one of the operations add, subtract, multiply or divide. We''re asked which operation is θ. This question comes down to some basic Arithmetic and TESTing VALUES. (1) If R =S, then R θ S = 0. With the information in Fact 1, ...” May 21, 2019 Rich.C@EMPOWERgmat.com posted a reply to Jack picked 76 apples. Of these, he sold 4y apples to... in the Data Sufficiency forum “Hi All, We''re told that Jack picked 76 apples - and of these, he sold 4Y apples to Juanita and 3T apples to Sylvia (and T and Y are positive integers.) and kept the remaining apples. We''re asked for the number of apples that he kept. To answer this question, we''ll need to know the values of T ...” May 21, 2019 Rich.C@EMPOWERgmat.com posted a reply to On a map, 1/2 inch represents 100 miles. in the Data Sufficiency forum “Hi All, We''re told that on a map, 1/2 inch represents 100 miles. We''re asked - according to this map - how many miles is City X from City Y. This question is based around the idea of ''unit conversions'' (which is really just basic Arithmetic. The prompt gives us the ratio of map-inches to ...” May 21, 2019 Brent@GMATPrepNow posted a reply to Question from mba.com mock test in the Problem Solving forum “The temperature of a certain cup of coffee 10 minutes after it was poured was 120 degrees Fahrenheit. So, 120 = 120 * 2^10)] + 60 Divide both sides by 60: 2 = 2 * 2^ f = 120 * 2^ The temperature of the coffee 30 minutes after it was poured was how many degrees Fahrenheit? f = 120 * 2^30)] + ...” May 21, 2019 Brent@GMATPrepNow posted a reply to OG #132 in the Problem Solving forum “We need to be able to create AT LEAST 12 codes (to represent the 12 countries). Let''s test the options. Can we get 12 or more color codes with 4 colors? Let''s see . . . 1-color codes = 4 (since there are 4 colors) 2-color codes = We need to choose 2 colors from 4. This can be ...” May 21, 2019 Brent@GMATPrepNow posted a reply to ps 500 test27 #16 in the Problem Solving forum “One approach: Salary Mary''s NET salary was x - y dollars (because Mary gave John y dollars) John''s NET salary was x + y dollars Hours worked Mary worked 8 hours John worked 10 hours In the end, John and Mary received the SAME hourly wage. So, John''s hourly wage = Mary''s ...” May 21, 2019 Brent@GMATPrepNow posted a reply to problem to solve in the Problem Solving forum “What we really have here is an algebra question requiring us to combine like terms. First, notice that K + K = 2K Using the same logic, 2^5 + 2^5 = 2(2^5) = (2^1)(2^5) = 2^6 Similarly, notice that M + M + M = 3M Using the same logic, 3^5 + 3^5 + 3^5 = 3(3^5) = (3^1)(3^5) = 3^6 So, 2^5 + ...” May 21, 2019 Brent@GMATPrepNow posted a reply to test 39 #13 in the Problem Solving forum “Here''s a related question to practice with: https://www.beatthegmat.com/intensity-scale-readings-t273997.html Cheers, Brent” May 21, 2019 Brent@GMATPrepNow posted a reply to test 38 #15 in the Problem Solving forum “red = 7 yellow = 5 green = 3 blue = 2 147,000 = (2)(2)(2)(3)(5)(5)(5)(7)(7) So, there are 3 blue beads, 1 green bead, 3 yellow beads and 2 red beads. Cheers, Brent” May 21, 2019 Brent@GMATPrepNow posted a reply to test35 # 15 in the Problem Solving forum “We want to determine how many integers end in 13 For example, 324713, 324813, 324913, 325013, . . . etc. Recognize that, for every 100 consecutive integers, only 1 will end in 13. There are 133,900 integers between 324,700 and 458,600 (since 458,600 - 324,700 = 133,900) Of those 133,900 ...” May 21, 2019 Brent@GMATPrepNow posted a reply to Help on PS problem- GMATprep in the Problem Solving forum “Let''s test the values using x = 0 So, we can reword the question as, For which of the following functions is f(0)=f(1-0) In other words, we''re looking for a function such that f(0) = f(1) A) f(x)=1-x f(0)=1-0 = 1 f(1)=1-1 = 0 Since f(0) doesn''t equal f(1), eliminate A B) f(x) = 1 - ...” May 21, 2019 Brent@GMATPrepNow posted a reply to Probability in the Problem Solving forum “We want: a) # of teams that include both John and Peter b) total # of 5-person teams possible a) # of teams that include both John and Peter Put John and Peter on the team (this can be accomplished in 1 way) Select the remaining 3 team-members from the remaining 7 players (this can be ...” May 21, 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 ...” May 21, 2019 Brent@GMATPrepNow posted a reply to A collection of 16 coins, each with a face value of either in the Problem Solving forum “Let D = the NUMBER of 10-cent coins Let Q = the NUMBER of 25-cent coins Notice that the VALUE of Q 25-cent coins = ($0.25)Q For example, the VALUE of six 25-cent coins = ($0.25)6 =$1.50 And the VALUE of ten 25-cent coins = ($0.25)10 =$2.50 etc Likewise, the VALUE of D 10-cent coins = ...”
May 21, 2019
Max@Math Revolution posted a new topic called If a=2b=6c for positive integers a, b, and c, which of the f in the Problem Solving forum
“[GMAT math practice question] If a=2b=6c for positive integers a, b, and c, which of the following could be the value of abc? A. 1000 B. 1230 C. 2250 D. 2367 E. 2488”
May 21, 2019
Max@Math Revolution posted a new topic called If m and n are positive integers, is m/n a terminating decim in the Data Sufficiency forum
“[GMAT math practice question] If m and n are positive integers, is m/n a terminating decimal? 1) m is divisible by 9 2) n is divisible by 30”
May 21, 2019
Brent@GMATPrepNow posted a new topic called Challenge question: Is positive integer p even? in the Data Sufficiency forum
“Is positive integer p even? (1) 4p has twice as many positive divisors as p has (2) 8p has 3 positive divisors more than p has Answer: A Source: www.gmatprepnow.com Difficulty level: 700+”
May 20, 2019
Rich.C@EMPOWERgmat.com posted a reply to If m and n are integers, what is the value of m + n ? in the Data Sufficiency forum
“Hi All, We''re told that M and N are INTEGERS. We''re asked for the value of M+N. This question can be solved with a mix of Algebra and TESTing VALUES. (1) (X + M)(X + N) = X^2 + 5X + (M)(N) and X ≠ 0. The equation in Fact 1 should get us thinking about a Quadratic and how we can ...”
May 20, 2019
Rich.C@EMPOWERgmat.com posted a reply to If a and b are integers, and b > 0, does (a−1)/(b+1) = in the Data Sufficiency forum
“Hi All, We''re told that A and B are INTEGERS, and B > 0. We''re asked if (A-1)/(B+1) = A/B. This is a YES/NO question and can be approached in a number of different ways, including by TESTing VALUES. (1) A = B - 4 IF.... B = 1, A = -3, then (-4)/(2) = -2 and (-3)/(1) = -3 and the ...”
May 20, 2019
Rich.C@EMPOWERgmat.com posted a reply to Is the sum of two integers divisible by 10 ? in the Data Sufficiency forum
“Hi All, We''re asked if the sum of two integers is divisible by 10. This is a YES/NO question can be solved by TESTing VALUES. (1) One of the integers is even. Fact 1 tells us about just one of the numbers; we know nothing about the other number. For organizational purposes, I''ll refer to ...”
May 20, 2019
Rich.C@EMPOWERgmat.com posted a reply to If p, r, and s are consecutive integers in ascending in the Data Sufficiency forum
“Hi All, We''re told that P, R and S are CONSECUTIVE integers in ASCENDING order and X is the AVERAGE (arithmetic mean) of the three integers. We''re asked for the value of X. To start, it''s worth noting that since we''re dealing with 3 CONSECUTIVE integers, the sum will always be ''3 ...”
May 20, 2019
Rich.C@EMPOWERgmat.com posted a reply to Three children inherited a total of X dollars. If the oldest in the Data Sufficiency forum
“Hi All, We''re told that three children inherited a TOTAL of X dollars, the oldest child inherited $7,000 MORE than the youngest child and the youngest child inherited$9,000 LESS than the middle child. We''re asked for the value of X. This question is built around some basic Arithmetic and ...”
May 20, 2019
Max@Math Revolution posted a new topic called If f(x)=x^4+4x^2+7, f(x)=g(x)^2+3 and g(x) > 0, then g(x)=? in the Problem Solving forum
“[GMAT math practice question] If f(x)=x^4+4x^2+7, f(x)=g(x)^2+3 and g(x) > 0, then g(x)=? A. x^2+1 B. x^2+2 C. x^2+3 D. x^2-1 E. x^2-2”
May 20, 2019
Max@Math Revolution posted a new topic called Is x > 0? in the Data Sufficiency forum
“[GMAT math practice question] Is x > 0? 1) |x| + |y| > |x + y| 2) |y| > y”
May 20, 2019
Max@Math Revolution posted a reply to (n+1)!f(n) = (n-1)!. What is the value of f(1) + f(2) + … in the Problem Solving forum
“=> (n+1)!f(n) = (n-1)! => (n-1)!*n*(n+1)f(n) = (n-1)! => n*(n+1)f(n) = 1 => f(n) = 1/{n(n+1)} => f(n) = 1/n – 1/(n+1) Thus f(1) + f(2) + … + f(100) = (1/1 – 1/2) + (1/2 – 1/3) + (1/3-1/4) + … + (1/99 – 1/100) + (1/100 – 1/101) = 1/1 – 1/101 = 100/101 ...”
May 20, 2019
Max@Math Revolution posted a reply to Each of A, B and C represents a one-digit integer. AB and BA in the Problem Solving forum
“=> Equating the units digits of BA + AB + AB and CAA gives either A + B + B = A or A + B + B = 10 + A. So, B = 5 or B = 0. Since BA is a two-digit integer, we must have B = 5. After carrying from the addition of the units digits, adding the tens digits yields B + A + A + 1 = 5 + A + A + 1 = ...”
May 20, 2019
Max@Math Revolution posted a reply to n is a positive odd integer. What is the value of 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 ...”
May 20, 2019
Max@Math Revolution posted a reply to What is the value 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 ...”
May 20, 2019
Marty Murray posted a reply to The fewer restrictions there are on the advertising of legal in the Critical Reasoning forum
“Often, the correct answer to an Inference question is based on a small portion of what the passage says, as is the correct answer to this question. In answering such a question, we have to notice that, even though the correct answer is directly related to only a small portion of what the passage ...”
May 18, 2019
Brent@GMATPrepNow posted a reply to In the figure above, if A, B, and C are the areas, respectiv in the Data Sufficiency forum
“Key concept: We''re told that the area of the BLUE circle = the area of the RED circle https://i.imgur.com/AZaIFeU.png This means we can say: A + B = B + C Now onto the question..... Target question: What is the value of B + C ? Statement 1: A + 2B + C = 24 Rewrite this as: (A + B) ...”
May 17, 2019
Max@Math Revolution posted a new topic called (n+1)!f(n) = (n-1)!. What is the value of f(1) + f(2) + … + in the Problem Solving forum
“[GMAT math practice question] (n+1)!f(n) = (n-1)!. What is the value of f(1) + f(2) + … + f(100)? A. 1/99 B. 1/100 C. 1/101 D. 99/100 E. 100/101”
May 17, 2019
Max@Math Revolution posted a reply to Sn=(Sn-1)Sn-2 , S1=-1 and S2=2. What is the value of S5? in the Problem Solving forum
May 17, 2019
Max@Math Revolution posted a new topic called n is a positive odd integer. What is the value of n? in the Data Sufficiency forum
“[GMAT math practice question] n is a positive odd integer. What is the value of n? 1) n, n + 2, n + 4 are prime numbers. 2) n - 1 is an even prime number.”
May 17, 2019
Max@Math Revolution posted a reply to What is the value of 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. Since we ...”
May 17, 2019
Rich.C@EMPOWERgmat.com posted a reply to What is the remainder when the positive integer n is divided in the Data Sufficiency forum
“Hi All, We''re told that N is a positive integers. We''re asked for the remainder when N is divided by 5. This question can be solved with a mix of Arithmetic and TESTing VALUES. (1) When N is divided by 3, the quotient is 4 and the remainder is 1. Fact 1 gives us remarkably specific ...”
May 16, 2019
Rich.C@EMPOWERgmat.com posted a reply to Is the point Q on the circle with center C ? in the Data Sufficiency forum
“Hi All, We''re asked if the point Q is on the circle with center C. This is a YES/NO question and can be approached with some logic (and a few examples/drawings might help). (1) R is a point on the circle and the distance from Q to R is equal to the distance from Q to C. Since C is the ...”
May 16, 2019
Rich.C@EMPOWERgmat.com posted a reply to Is the average (arithmetic mean) of the numbers x, y, and z in the Data Sufficiency forum
“Hi All, We''re asked if the average (arithmetic mean) of the numbers X, Y, and Z is GREATER than Z. This is a YES/NO question and can be approached with a mix of Arithmetic and TESTing VALUES. To start, we can ''rewrite'' the question a bit: Is (X+Y+Z)/3 > Z? Is (X+Y+Z) > 3Z? Is (X+Y) ...”
May 16, 2019
Rich.C@EMPOWERgmat.com posted a reply to What number is 6 more than x + y ? in the Data Sufficiency forum
“Hi All, We''re asked what number is 6 MORE than (X+Y). This question can be approached in a couple of different ways, including by TESTing VALUES. It''s worth noting that the prompt does NOT place any restrictions on X and Y, so they could be positive, negative, 0, fractions, etc. (1) Y is 3 ...”
May 16, 2019
Rich.C@EMPOWERgmat.com posted a reply to If x is an integer greater than 0, what is the remainder in the Data Sufficiency forum
“Hi All, We''re told that X is an INTEGER GREATER than 0. We''re asked for the remainder when X is divided by 4. This question is based around some basic Arithmetic rules (and you can TEST VALUES to define the patterns involved). To start, here are the first several positive integers - and what ...”
May 16, 2019
ceilidh.erickson posted a reply to A 3-digit positive integer consists of non zero digits. If in the Problem Solving forum
“There are 3 configurations that would yield a 3-digit integer with 2 of the same digit, one different digit: same]same]different] same]different]same] different]same]same] So, let''s calculate the number of combinations for one of these: same]same]different] There would be 9 non-zero digits ...”
May 16, 2019
ceilidh.erickson posted a reply to The recording industry is fighting a losing battle: it in the Critical Reasoning forum
“For more on this YES / NO test for EVALUATE questions, see: https://www.beatthegmat.com/goronian-lawmaker-goronia-s-cheese-importation-board-the-a-t305457.html#823815 https://www.beatthegmat.com/over-the-last-five-years-demand-for-hotel-rooms-in-cenopoli-t305855.html#825344 ...”
May 16, 2019
ceilidh.erickson posted a reply to The recording industry is fighting a losing battle: it in the Critical Reasoning forum
“When we''re asked to EVALUATE an argument, it''s implied that there is currently missing information - UNSTATED ASSUMPTIONS - that would be needed for the argument to logically cohere. Premises: - recording industry does not have the resources to prosecute all of the individuals who illegally ...”
May 16, 2019
ceilidh.erickson posted a reply to In the nation of Partoria, large trucks currently account in the Critical Reasoning forum
“There are several logical flaws in this argument: Premises: Trucks with three trailers had less than a third of the accident rate of single- and double-trailer trucks Conclusion: one way for Partoria to reduce highway deaths would be to require shippers to increase their use of triple-trailer ...”
May 16, 2019
ceilidh.erickson posted a reply to How many perfect squares are less than the integer $$d$$? in the Data Sufficiency forum
“The best way to approach this problem is to test cases: How many perfect squares are less than the integer d? 1) 23 < d < 33 if d = 32, there are 5 perfect squares less than d: 1, 4, 9, 16, 25 if d = 24, there are 4 perfect squares less than d: 1, 4, 9, 16 Insufficient 2) 27 < ...”
May 16, 2019
ceilidh.erickson posted a reply to In a set of five consecutive integers, which of the in the Problem Solving forum
“OP: there is an error in this question. Are you sure it''s transcribed correctly? As written there is no correct answer. In any consecutive (or evenly spaced) set, the median is always equal to the average. If we want to change the average *without* changing the median, we must make it a ...”
May 16, 2019
ceilidh.erickson posted a reply to Fedora Convertibles began selling the Freewheeler - its in the Critical Reasoning forum
“When we''re asked to EVALUATE an argument, it''s implied that there is currently missing information - UNSTATED ASSUMPTIONS - that would be needed for the argument to logically cohere. Premise: Freewheeler’s sales for May, June, July, and August totaled over 50,000. Conclusion: As a ...”
May 16, 2019
ceilidh.erickson posted a reply to The pioneering research of Lewis Latimer and Thomas Edison, in the Sentence Correction forum
“This question is testing MODIFIERS. If we have an "and" linking two nouns (e.g. "Latimer and Edison") followed by a noun modifier (e.g. "who"), it''s implied that both nouns are being modified. So in "... Lewis Latimer and Thomas Edison, who became ...”
May 16, 2019
Brent@GMATPrepNow posted a reply to Bite-sized video lessons from GMAT Prep Now in the GMAT Math forum
“Data Sufficiency lesson #7: - The Table Method Video : https://www.youtube.com/watch?v=lYfTiRIG_k4 Cheers, Brent”
May 16, 2019
Max@Math Revolution posted a new topic called Each of A, B and C represents a one-digit integer. AB and BA in the Problem Solving forum
“[GMAT math practice question] Each of A, B and C represents a one-digit integer. AB and BA are two-digit integers, and CAA is a three-digit integer. If BA + AB + AB = CAA, what is the value of A? A. 1 B. 2 C. 3 D. 4 E. 5”
May 16, 2019
Max@Math Revolution posted a reply to n is an integer. What is the units digit of n^5-5n^3+4n? in the Problem Solving forum
“=> n^5-5n^3+4n = n(n^4-5n^2+4) = n(n^2-1)(n^2-4) = n(n+1)(n-1)(n-2)(n-2) = (n-2)(n-1)n(n+1)(n+2). Thus, n^5-5n^3+4n is a product of five consecutive integers. Since it is divisible by 2, 3, 4, and 5, it is a multiple of 10. Thus, its units digits is 0. Therefore, the answer is A. ...”
May 16, 2019
Max@Math Revolution posted a new topic called What is the value of x? in the Data Sufficiency forum
“[GMAT math practice question] What is the value of x? 1) |x+y| = |x-y| 2) |y| > y”
May 16, 2019
Max@Math Revolution posted a reply to If k/mn, where k, m and n are positive integers, is a fracti 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 ...”
May 16, 2019
Rich.C@EMPOWERgmat.com posted a reply to A certain painting job requires a mixture of yellow, green, in the Data Sufficiency forum
“Hi All, We''re told that a certain painting job requires a mixture of yellow, green, and white paint and that 12 quarts of paint are needed for the job. We''re asked for the number of quarts of GREEN paint that are needed. This question can be answered with ratio-based math and TESTing VALUES. ...”
May 16, 2019
Rich.C@EMPOWERgmat.com posted a reply to A noncompressible ball in the shape of a sphere is to in the Data Sufficiency forum
“Hi All, We''re told that a non-compressible ball in the shape of a SPHERE is to be passed through a SQUARE opening in a board. We''re asked for the perimeter of the opening. While this question might seem a bit quirky, it''s actually based on some basic Geometry rules. To start, it''s worth ...”
May 16, 2019
Rich.C@EMPOWERgmat.com posted a reply to After the first two terms in a sequence of numbers, each in the Data Sufficiency forum
“Hi All, We''re told that after the first two terms in a sequence of numbers, each term in the sequence is formed by adding ALL of the preceding terms. We''re asked if 12 is the fifth term in the sequence? This is a YES/NO question and can be approached with some basic Arithmetic and ...”
May 16, 2019
Rich.C@EMPOWERgmat.com posted a reply to A company produces a certain toy in only 2 sizes, small or in the Data Sufficiency forum
“Hi All, We''re told that a company produces a certain toy in only 2 sizes, small or large, and in only 2 colors, red or green - and that for each size, there are EQUAL numbers of red and green toys in a certain production lot. We''re asked for the fraction of the total number of GREEN toys that ...”
May 16, 2019
Rich.C@EMPOWERgmat.com posted a reply to If a merchant purchased a sofa from a manufacturer for $400 in the Data Sufficiency forum “Hi All, We''re told that a merchant purchased a sofa from a manufacturer for$400 and then sold it. We''re asked for the selling price of the sofa. This question is based around a mix of basic Arithmetic and Algebra. (1) The selling price of the sofa was greater than 140 percent of the ...”
May 16, 2019
Brent@GMATPrepNow posted a reply to If Mary always takes the same route to work, how long did it in the Data Sufficiency forum
“Target question: How long did it take Mary to get to work on Friday? Statement 1: It took Mary 20 minutes to get to work on Thursday. Clearly, we cannot use this information to answer the target question with certainty. Statement 1 is NOT SUFFICIENT Statement 2: Mary''s average speed ...”
May 15, 2019
Max@Math Revolution posted a new topic called Sn=(Sn-1)Sn-2 , S1=-1 and S2=2. What is the value of S5? in the Problem Solving forum
“n-1)^{Sn-2} , S1=-1 and S2=2. What is the value of S5? A. 1/4 B. 1/2 C. 1 D. 2 E. 4”
May 15, 2019
Max@Math Revolution posted a reply to If 0 ＜ x+1 ＜ 1, which of the following lists is written in the Problem Solving forum
“=> Plug in x = -1/2. Then x^{-2} = 4, x^{-1}= -2 and x^2 = 1/4 Thus, x^{-1}< x < x^2 < 1 < x^{-2}. Therefore, C is the answer. Answer: C ”
May 15, 2019
Max@Math Revolution posted a new topic called What is the value of n? in the Data Sufficiency forum
“[GMAT math practice question] What is the value of n? 1) n is the product of 2 different prime numbers less than 15 2) n and 210 are relatively prime”
May 15, 2019
Max@Math Revolution posted a reply to If n is a positive integer, is n^2+2n+44 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 ...”
May 15, 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. ...”
May 15, 2019
Rich.C@EMPOWERgmat.com posted a reply to A rectangular solid has length, width, and height of L cm in the Data Sufficiency forum
“Hi All, We''re told that a rectangular solid has length, width, and height of L cm, W cm, and H cm, respectively. We''re asked if these dimensions are increased by X%, Y%, and Z%, respectively, what would be the PERCENTAGE INCREASE in the total SURFACE AREA of the solid. This question is based ...”
May 14, 2019
Rich.C@EMPOWERgmat.com posted a reply to The length, width, and height of a rectangular box in the Data Sufficiency forum
“Hi All, We''re told that the length, width, and height of a rectangular box, in centimeters, are L, W, and H, respectively, the VOLUME of this box is V cubic centimeters and the TOTAL SURFACE AREA of the 6 sides of this box is A square centimeters. We''re asked for the value of V/A. This ...”
May 14, 2019
Rich.C@EMPOWERgmat.com posted a reply to A paint mixture was formed by mixing exactly 3 colors of in the Data Sufficiency forum
“Hi All, We''re told that a paint mixture was formed by mixing exactly 3 colors of paint. By volume, the mixture was X% blue paint, Y% green paint, and Z% red paint and exactly 1 gallon of BLUE paint and 3 gallons of RED paint were used. We''re asked for the number of gallons of green paint that ...”
May 14, 2019
Rich.C@EMPOWERgmat.com posted a reply to If 2.00X and 3.00Y are 2 numbers in decimal form with thousa in the Data Sufficiency forum
“Hi All, We''re told that 2.00X and 3.00Y are 2 numbers in DECIMAL form with THOUSANDTHS digits of X and Y, respectively. We''re asked if 3(2.00X) > 2(3.00Y). This is a YES/NO question and can be solved with a mix of Arithmetic and TESTing VALUES. There''s a great built-in ''shortcut'' that we ...”
May 14, 2019
Rich.C@EMPOWERgmat.com posted a reply to Three roommates—Bela, Gyorgy, and Janos—together saved m in the Data Sufficiency forum
“Hi All, We''re told that three roommates - Bela, Gyorgy, and Janos - together saved money for a trip. The amount that Bela saved was equal to 8% of his monthly income and the amount that Gyorgy saved was exactly 1/3 of the TOTAL amount saved by all 3 roommates. We''re asked for the total amount ...”
May 14, 2019
Brent@GMATPrepNow posted a reply to x-4=z y-x=8 8-z=t For the system of equations given, what in the Data Sufficiency forum
“Target question: What is the value of z? Statement 1: x = 7 Scanning the three given equations, we see that equation i is all we need to determine the value of z i) x - 4 = z Replace x with 7 to get: 7 - 4 = z So, z = 3 Since we can answer the target question with certainty, statement 1 ...”
May 14, 2019
Max@Math Revolution posted a new topic called n is an integer. What is the units digit of n^5-5n^3+4n? in the Problem Solving forum
“[GMAT math practice question] n is an integer. What is the units digit of n^5-5n^3+4n? A. 0 B. 2 C. 4 D. 6 E. 8”
May 14, 2019
Max@Math Revolution posted a new topic called If k/mn, where k, m and n are positive integers, is a fracti in the Data Sufficiency forum
“[GMAT math practice question] If k/mn, where k, m and n are positive integers, is a fraction in its lowest terms, is k/mn a terminating decimal? 1) 1/m is a terminating decimal 2) 1/n is a terminating decimal”
May 14, 2019
Rich.C@EMPOWERgmat.com posted a reply to 7, 9, 6, 4, 5, x If x is a number in the list above in the Data Sufficiency forum
“Hi All, We''re told that X is a number in the list (7, 9, 6, 5, 4, X). We''re asked for the MEDIAN of the list. This question can be solved with Stats rules and TESTing VALUES. To start though, since there are six values in the list, the MEDIAN will be the AVERAGE of the two ''middle terms'' ...”
May 13, 2019
Rich.C@EMPOWERgmat.com posted a reply to In the figure above, triangle PQR has angle measures as in the Data Sufficiency forum
“Hi All, We''re told that the triangle PQR has angle measures as shown. We''re asked if X is less than Y. This is a YES/NO question and is based around a specific Triangle rule (re: in simple terms, the bigger the angle, the bigger the side that''s across from it). Since Angle R is 58 degrees, ...”
May 13, 2019
Rich.C@EMPOWERgmat.com posted a reply to The 9 squares above are to be filled with x's and o's in the Data Sufficiency forum
“Hi All, We''re told that the 9 squares above are to be filled with X''s and O''s, with only one symbol in each square. We''re asked for the number of squares that will contain an X. This question is based around some simple Arithmetic and logic - although you might find it useful to draw a few ...”
May 13, 2019
Rich.C@EMPOWERgmat.com posted a reply to If a building has 6,000 square meters of floor space in the Data Sufficiency forum
“Hi All, We''re told that a building has 6,000 square meters of floor space. We''re asked for the number offices in the building. Since we''re given the total floor space, to answer this question, we''ll need to have some really specific data about the respective size(s) of the offices. This ...”
May 13, 2019
Rich.C@EMPOWERgmat.com posted a reply to In the figure above, RST is a triangle with angle measures in the Data Sufficiency forum
“Hi All, We''re told that In the figure above, RST is a triangle with angle measures as shown and PRTQ is a line segment. We''re asked for the value of (X+Y). This question is built around a couple of Geometry lines involving Triangles and Lines. To start, the angles in the triangle (re: s, r and ...”
May 13, 2019
Brent@GMATPrepNow posted a reply to In triangle JKL shown above, what is the length of segment in the Data Sufficiency forum
“KEY CONCEPT: 30-60-90 triangles are known as special right triangles, and we know quite a bit about this kind of triangle Target question: What is the length of segment JL ? Statement 1: JK = 10 https://i.imgur.com/sKEFT1R.png Compare ΔJKL with the BASE 30-60-90 triangle. Their ...”
May 13, 2019
Brent@GMATPrepNow posted a reply to A line that passes through (–1, –4) and (3, k) has a slo in the Problem Solving forum
“Slope of line between the points (x1, y1) and (x2, y2) = (y2 - y1)/(x2 - x1) So, we can write: k = [k - (-4)]/[3 - (-1)] Simplify: (k + 4)/4 = k Multiply both sides by 4 to get: k + 4 = 4k Subtract k from both sides to get: 4 = 3k Divide both sides by 3 to get: 4/3 = k Answer: C Cheers, ...”
May 13, 2019
Brent@GMATPrepNow posted a reply to If the two digit integers M and N are positive and have the in the Problem Solving forum
“This question relies on our ability to determine the VALUE of any 2-digit number. For example, what is the VALUE of 83? For many of us, it has been a very long time since we examined this (we learned this when we were 5 or 6). Most of us just say that 83 has a value of 83, but 83 is really just ...”
May 13, 2019
Max@Math Revolution posted a new topic called If 0 ＜ x+1 ＜ 1, which of the following lists is written in in the Problem Solving forum
“[GMAT math practice question] If 0 ＜ x+1 ＜ 1, which of the following lists is written in ascending order? A. x, x^{-1}, x^2, 1, x^{-2} B. x^{-2}, x, x^2, 1, x^{-1} C. x^{-1}, x, x^2, 1, x^{-2} D. x^{-1}, x^2, x, 1, x^{-2} E. x^{-1}, x, x^2, x^{-2}, 1”
May 13, 2019
Max@Math Revolution posted a new topic called If n is a positive integer, is n^2+2n+44 divisible by 4? in the Data Sufficiency forum
“[GMAT math practice question] If n is a positive integer, is n^2+2n+44 divisible by 4? 1) n is an even integer. 2) n^2 is divisible by 144”
May 13, 2019
Max@Math Revolution posted a reply to p and q are the roots of the equation x^2+ax+b=0. What is an in the Problem Solving forum
“=> If p and q are roots of the quadratic equation x^2 + ax + b = 0, then the quadratic equation can be written as (x-p)(x-q) = 0 or x^2 –(p+q)x + pq = 0. Thus, p + q = -a and pq = b. So, p^2q + pq^2 = pq(p+q) = b*(-a) = -ab Therefore, B is the answer. Answer: B ”
May 13, 2019
Max@Math Revolution posted a reply to What is the product of all roots of the equation √x+1 = x- in the Problem Solving forum
“=> √x+1 = x-√x-1 => 2√x = x-2 => 4x = (x-2)^2, after squaring both sides, => 4x = x^2-4x+4 => x^2-8x+4 = 0 If p and q are roots of a quadratic equation, then the quadratic equation is (x-p)(x-q) = 0 or x^2 –(p+q)x + pq = 0. The constant term pq is the product of ...”
May 13, 2019
Max@Math Revolution posted a reply to Is triangle ABC 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 ...”
May 13, 2019
Max@Math Revolution posted a reply to In the xy-plane a circle C has (0,0) as its center and 5 as 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 ...”
May 13, 2019
Rich.C@EMPOWERgmat.com posted a reply to In the figure above, if A, B, and C are the areas, respectiv in the Data Sufficiency forum
“Hi All, We''re told that in the figure above, A, B, and C are the areas, respectively, of the three non-overlapping regions formed by the intersection of two circles of EQUAL area. We''re asked for the value of B + C. While this question might look like it might be step-heavy, there are some ...”
May 12, 2019
Rich.C@EMPOWERgmat.com posted a reply to In the figure above, the vertices of triangle OPQ and in the Data Sufficiency forum
“Hi All, We''re told that In the figure above, the vertices of triangle OPQ and triangle QRS have coordinates as indicated. We''re asked if triangle OPQ and triangle QRS have equal areas. This is a YES/NO question and is built on Geometry rules (although you might find it useful to TEST VALUES). ...”
May 12, 2019
Rich.C@EMPOWERgmat.com posted a reply to In triangle JKL shown above, what is the length of segment in the Data Sufficiency forum
“Hi All, Based on the triangle JKL above, we know that we''re dealign with a 30/60/90 right triangle. We''re asked for the length of segment JL. The 30/60/90 triangle has a specific ''ratio of sides'' (re: X : X√3 : 2X), meaning that if we know 1 of the sides, then we can determine the lengths ...”
May 12, 2019
Rich.C@EMPOWERgmat.com posted a reply to If, in the figure above, ABCD is a rectangular region in the Data Sufficiency forum
“Hi All, We''re told that in the figure above, ABCD is a rectangular region. We''re asked for the value of the ratio of (area of triangle EDA)/(area of triangle EBC)? This question is based on a couple of Geometry rules. It''s worth noting that all 3 triangles (EDA, EBC and EDC) all have the SAME ...”
May 12, 2019
Rich.C@EMPOWERgmat.com posted a reply to A six-sided mosaic contains 24 triangular pieces of tile in the Data Sufficiency forum
“Hi All, We''re told that a six-sided mosaic contains 24 triangular pieces of tile of the SAME size and shape, as shown in the figure above and that the sections of tile fit together perfectly. We''re asked for the total square centimeters of tile in the mosaic. While this question might look a ...”
May 12, 2019
Brent@GMATPrepNow posted a reply to If n is an integer greater than 10, then the expression (n^2 in the Problem Solving forum
“-----ASIDE--------------------- There''s a nice rule says: The product of k consecutive integers is divisible by k, k-1, k-2,...,2, and 1 So, for example, the product of any 5 consecutive integers will be divisible by 5, 4, 3, 2 and 1 Likewise, the product of any 11 consecutive integers will be ...”
May 12, 2019
Rich.C@EMPOWERgmat.com posted a reply to Is x an integer? in the Data Sufficiency forum
“Hi All, We''re asked if X is an INTEGER. This is a YES/NO question. This question is built around some standard math rules and Number Properties. (1) X^3 = 8 With Fact 1, we''re cubing the value of X and ending with a POSITIVE value - thus, X MUST be positive. Here, the value of X = +2 ...”
May 11, 2019
Rich.C@EMPOWERgmat.com posted a reply to In any sequence of n nonzero numbers, a pair of consecutive in the Data Sufficiency forum
“Hi All, We''re told that in any sequence of N NON-ZERO numbers, a pair of consecutive terms with opposite signs represents a sign change (for example, the sequence -2, 3, -4, 5 has three sign changes). We''re asked if the sequence of nonzero numbers s1, s2, s3, . . . , sn has an EVEN number of ...”
May 11, 2019
Rich.C@EMPOWERgmat.com posted a reply to If each side of parallelogram P has length 1, what is the in the Data Sufficiency forum
“Hi All, We''re told that each side of parallelogram P has length 1. We''re asked for the area of P. This is a great ''concept question'', meaning that if you know the concepts involved, then you don''t actually have to do much math to get the correct answer. Here, since we know all 4 sides of ...”
May 11, 2019
Rich.C@EMPOWERgmat.com posted a reply to In the figure above, what is the area of region PQRST ? in the Data Sufficiency forum
“Hi All, We''re asked for the area of region PQRST. This question is based around a couple of Geometry rules. To properly find the area, we can break this shape into 2 pieces (a rectangle and a triangle), so we need to know the dimensions of the rectangle and the exact type of triangle - since we ...”
May 11, 2019
Rich.C@EMPOWERgmat.com posted a reply to If x and y are the lengths of the legs of a right triangle, in the Data Sufficiency forum
“Hi All, We''re told that X and Y are the lengths of the legs of a RIGHT triangle. We''re asked for the value of (X)(Y). This question can be solved with a mix of Geometry rules and TESTing VALUES. (1) The hypotenuse of the triangle is 10√2. With the information in Fact 1 - and the ...”
May 11, 2019
Brent@GMATPrepNow posted a reply to If x and y are the lengths of the legs of a right triangle, in the Data Sufficiency forum
“ Given: x and y are the lengths of the legs of a right triangle We have something like this: https://i.imgur.com/VxCexHO.png Target question: What is the value of xy? Statement 1: The hypotenuse of the triangle is There are infinitely-many different right triangles that meet this ...”
May 11, 2019
Brent@GMATPrepNow posted a reply to In how many different ways can a soccer team finish the in the Problem Solving forum
“Question rephrased: In how many different ways can we arrange the letters WWWLLD -------------ASIDE-------------------------------------- When we want to arrange a group of items in which some of the items are identical, we can use something called the If there are n objects where A of them are ...”
May 11, 2019
Rich.C@EMPOWERgmat.com posted a reply to If a and b are integers, is a^5 < 4^b ? in the Data Sufficiency forum
“Hi All, We''re told that A and B are INTEGERS. We''re asked if A^5 is less than 4^B. This question can be approached with a mix of Number Properties and TESTing VALUES. To start, it''s worth noting that raising +4 to ANY power will lead to a POSITIVE value (for example, 4^0 = 1, 4^-1 = 1/4, ...”
May 10, 2019
Rich.C@EMPOWERgmat.com posted a reply to The total price of 5 pounds of regular coffee in the Data Sufficiency forum
“Hi All, We''re told that the total price of 5 pounds of regular coffee and 3 pounds of decaffeinated coffee was $21.50. We''re asked for the price of the 5 pounds of regular coffee. The information in the first sentence can be used to create a 2 variable equation, which should get us thinking ...” May 10, 2019 Rich.C@EMPOWERgmat.com posted a reply to A certain list, L, contains a total of n numbers, in the Data Sufficiency forum “Hi All, We''re told that List L contains a total of N numbers, NOT necessarily DISTINCT, that are arranged in INCREASING order and L1 is the list consisting of the first N1 numbers in L and L2 is the list consisting of the last N2 numbers in L. We''re asked if 17 is a MODE for L. It''s worth ...” May 10, 2019 Rich.C@EMPOWERgmat.com posted a reply to In the figure above, PQRT is a rectangle. What is the length in the Data Sufficiency forum “Hi All, We''re told that PQRT is a rectangle. We''re asked fo the length of segment PQ. This question can be solved with a mix of Geometry rules and TESTing VALUES. To start, when dealing with complex shapes, it helps to break the shape down into ''pieces'': here, we''re dealing with a ...” May 10, 2019 Rich.C@EMPOWERgmat.com posted a reply to Jones has worked at Firm X twice as many years as Green in the Data Sufficiency forum “Hi All, We''re told that Jones has worked at Firm X TWICE as many years as Green, and Green has worked at Firm X four years LONGER than Smith. We''re asked for the number of years that Green has worked at Firm X. This question can be approached in a couple of different ways, but there''s a ...” May 10, 2019 Brent@GMATPrepNow posted a reply to Jones has worked at Firm X twice as many years as Green in the Data Sufficiency forum “We can also solve the question using one variable Given: Jones has worked at Firm X twice as many years as Green, and Green has worked at Firm X four years longer than Smith. Let G = the number of years Green worked at Firm X So, G - 4 = the number of years Smith worked at Firm X (since ...” May 10, 2019 Brent@GMATPrepNow posted a reply to In the below addition A, B, C, D, E, F, and G represent the in the Problem Solving forum “If we add two 2-digit numbers and the sum is a 3-digit number, then the 3-digit number must start with a 1. So, E = 1 In order for the sum to be a 3-digit number, A+C must be greater than 9 So, we have two options: EITHER A and C are 5 and 6, OR A and C are 4 and 6 If A and C are 5 and 6, ...” May 10, 2019 Max@Math Revolution posted a new topic called p and q are the roots of the equation x^2+ax+b=0. What is an in the Problem Solving forum “[GMAT math practice question] p and q are the roots of the equation x^2+ax+b=0. What is an expression for p^2q + pq^2 in terms of a and b? A. ab B. -ab C. a^2b D. ab^2 E. a^2b^2” May 10, 2019 Max@Math Revolution posted a reply to The sum of two numbers is 1 and their product is -1. What is in the Problem Solving forum “=> Let the numbers be x and y. Then x + y = 1 and xy = -1. Since (x+y)^2 = x^2 + 2xy + y^2 = x^2 + y^2 – 2, we have x^2 + y^2 = 3, and x^3 + y^3 = (x+y)(x^2-xy+y^2) = 1*(x^2+ 1 + y^2) = x^2+y^2+1 = 4. Therefore, the answer is D. Answer: D ” May 10, 2019 Max@Math Revolution posted a new topic called Is triangle ABC a right triangle? in the Data Sufficiency forum “[GMAT math practice question] Is triangle ABC a right triangle? 1) The perimeter of triangle ABC is 12 2) The length of the shortest side of triangle ABC is 3” May 10, 2019 Max@Math Revolution posted a new topic called Is triangle ABC a right triangle? in the Data Sufficiency forum “[GMAT math practice question] Is triangle ABC a right triangle? 1) The perimeter of triangle ABC is 12 2) The length of the shortest side of triangle ABC is 3” May 10, 2019 Max@Math Revolution posted a reply to Is |x-1| < |x-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 ...” May 10, 2019 Rich.C@EMPOWERgmat.com posted a reply to The figure above represents a box that has the shape of a in the Data Sufficiency forum “Hi All, We''re told that the figure above represents a box that has the shape of a CUBE. We''re asked for the is the volume of the cube. While this question might appear a bit ''scary'', there''s a great ''logic shortcut'' built into it - since we''re dealing with a CUBE, we know that all of the ...” May 9, 2019 Rich.C@EMPOWERgmat.com posted a reply to Is x = y? in the Data Sufficiency forum “Hi All, We''re asked if X = Y. This is a YES/NO question can be solved with a mix of Arithmetic and TESTing VALUES. 1) (2X/3) - (Y/3) = 1/3 Since each value in this equation is divided by 3, we can ''simplify'' the equation by multiplying each term by 3. This gives us: 2X - Y = 1 2X = Y ...” May 9, 2019 Rich.C@EMPOWERgmat.com posted a reply to If a and b are constants, is the expression in the Data Sufficiency forum “Hi All, We''re told that A and B are constants. We''re asked if the expression (X+B)/(√(X+A)) is "defined" for x = -2. This is a YES/NO question and is a great ''concept'' question - meaning that you don''t have to do much math if you understand the concepts involved. For the given ...” May 9, 2019 Rich.C@EMPOWERgmat.com posted a reply to Is quadrilateral PQRS a parallelogram? in the Data Sufficiency forum “Hi All, We''re asked if quadrilateral PQRS is a parallelogram? This is a YES/NO question can be answered with a bit of logic (and a couple of drawings). By definition, a parallelogram must have 4 sides and each pair of ''opposite'' sides must be parallel. 1) Adjacent sides PQ and QR have the ...” May 9, 2019 Rich.C@EMPOWERgmat.com posted a reply to If xyz ≠ 0, what is the value of in the Data Sufficiency forum “Hi All, We''re told that If (X)(Y)(Z) ≠ 0. We''re asked for the value of (X^4)(Z^2) / (Z^2)(Y^2). This question can be approached in a number of different ways, including Algebra and TESTing VALUES. To start, it''s worth noting that none of the given variables can equal 0 and the term ...” May 9, 2019 Brent@GMATPrepNow posted a reply to If xyz ≠ 0, what is the value of in the Data Sufficiency forum “Target question: What is the value of (x⁴z²)/(z²y²)? This is a good candidate for rephrasing the target question. Since z ≠ 0, we know that z² ≠ 0 So, we can safely take (x⁴z²)/(z²y²) and divide top and bottom by z² to get: x⁴/y² REPHRASED target question: What is the value ...” May 9, 2019 Brent@GMATPrepNow posted a reply to Is quadrilateral PQRS a parallelogram? in the Data Sufficiency forum “Target question: Is quadrilateral PQRS a parallelogram? If you recognize that each statement on its own is not sufficient, we can jump straight to . . . Statements 1 and 2 combined There are infinitely-many quadrilaterals that satisfy BOTH statements. Here are two: Case a: PQRS could ...” May 9, 2019 Brent@GMATPrepNow posted a reply to A lecture course consists of 595 students. The students are in the Problem Solving forum “In order to have an EQUAL number of students in each section, the number of students per section MUST BE A FACTOR of 595 Let''s do some prime factorization 595 = (5)(7)(17) From the prime factorization, we can see that answer choice A, B, D and E are all factors of 595 Answer: C Cheers, ...” May 9, 2019 Brent@GMATPrepNow posted a reply to If a and b are constants, is the expression in the Data Sufficiency forum “Target question: Is the expression defined for x = –2? This is a great candidate for rephrasing the target question. If x = -2, then the expression becomes (-2)+b/√(-2+a) There are two ways in which the expression(-2)+b/√(-2+a) is NOT defined: case i) If a = 2, then the fraction''s ...” May 9, 2019 Brent@GMATPrepNow posted a reply to Is x = y? in the Data Sufficiency forum “Target question: Is x = y? Statement 1: 2x/3 - y/3 = 1/3 Multiply both sides by 3 to get: 2x - y = 1 There are several values of x and y that satisfy this equation. Here are two: Case a: x = 1 and y = 1. In this case, the answer to the target question is YES, it is the case that x = y ...” May 9, 2019 Brent@GMATPrepNow posted a reply to The figure above represents a box that has the shape of a in the Data Sufficiency forum “Target question: What is the volume of the box? IMPORTANT: For geometry Data Sufficiency questions, we are typically checking to see whether the statements "lock" a particular angle, length, or shape into having just one possible measurement. This concept is discussed in much greater ...” May 9, 2019 Brent@GMATPrepNow posted a reply to In the figure above, PQRT is a rectangle. What is the length in the Data Sufficiency forum “Let''s assign some variables to some of the lengths... https://i.imgur.com/BpaiRKm.png Target question: What is the value of x? Statement 1: The area of region PQRS is 39 and TS = 6. Region PQRS is a TRAPEZOID Area of trapezoid = (height)(base1 + base2)/2 So, we get: (x)(y + z)/2 = 39 ...” May 9, 2019 Brent@GMATPrepNow posted a reply to Charlie takes 2.5 hours to fly from Los Angeles to Mexico Ci in the Problem Solving forum “Here''s how I would answer this in my head Average speed = total distance/total time = 1200/2.5 = 2400/5 = 4800/10 = 480 Answer: D Cheers, Brent” May 9, 2019 Max@Math Revolution posted a new topic called What is the product of all roots of the equation √x+1 = x-√x in the Problem Solving forum “[GMAT math practice question] What is the product of all roots of the equation √x+1 = x-√x-1? A. 1 B. 2 C. 3 D. 4 E. 5” May 9, 2019 Max@Math Revolution posted a reply to A book has 1000 pages numbered 1, 2, 3, …, and so on. How in the Problem Solving forum “=> The page numbers 2, 12, 20, 21, 22, … , 29, 32, 42, … , 92 contain 19+1 = 20 copies of the digit, 2. The page numbers 102, 112, 120, 121, … , 129, 132, 142, … , 192 similarly contain 20 copies of the digit 2. The page numbers 200, 201, … , 299 contain 120 copies of the digit, 2. ...” May 9, 2019 Max@Math Revolution posted a new topic called In the xy-plane a circle C has (0,0) as its center and 5 as in the Data Sufficiency forum “[GMAT math practice question] In the xy-plane a circle C has (0,0) as its center and 5 as its radius. If line K is tangent to the circle C, what is the equation of line K? 1) Line K is tangent to the circle C at the point (0,5) 2) Line K passes through the point (5,5).” May 9, 2019 Max@Math Revolution posted a reply to If x, y, and z are integers, is xyz a multiple of 6? 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 ...” May 9, 2019 Brent@GMATPrepNow posted a reply to What amount did Jean earn from the commission on her sales in the Data Sufficiency forum “Target question: What amount did Jean earn from the commission on her sales in the FIRST HALF of 1988 ? Statement 1: In 1988 Jean''s commission was 5 percent of the total amount of her sales. We don''t know her total sales amount in 1988, AND we don''t know what happened in the FIRST HALF of ...” May 8, 2019 Max@Math Revolution posted a new topic called The sum of two numbers is 1 and their product is -1. What is in the Problem Solving forum “[GMAT math practice question] The sum of two numbers is 1 and their product is -1. What is the sum of their cubes? A. 1 B. 2 C. 3 D. 4 E. 5” May 8, 2019 Max@Math Revolution posted a reply to What is the remainder when the product of the first 10 prime in the Problem Solving forum “=> 2, 3, 5, 7, 11, 13, 17, 19, 23 and 29 are the first 10 prime numbers. Of these, only 2 is an even integer. Their product is an even number, but it is not divisible by 4. Thus, the product has remainder 2 when it is divided by 4. Therefore, C is the answer. Answer: C ” May 8, 2019 Max@Math Revolution posted a new topic called Is |x-1| < |x-3|? in the Data Sufficiency forum “[GMAT math practice question] Is |x-1| < |x-3|? 1) x < 2 2) x > -2” May 8, 2019 Max@Math Revolution posted a reply to Is x + y < -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. Since we ...” May 8, 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. ...” May 8, 2019 Brent@GMATPrepNow posted a reply to Six shipments of machine parts were shipped from a factory o in the Data Sufficiency forum “We might be able to solve this one faster by first converting the fractions to decimals. S1=0.25 S2=0.2 S3=0.17 (approx) S4=0.15 S5=0.13 (approx) S6=0.1 Statement 1: S2 and S4 were shipped on the first truck. First truck has 0.2 + 0.15 = 0.35 Since the first truck holds more than 0.5, ...” May 7, 2019 Brent@GMATPrepNow posted a reply to If a and b are integers, is a^5 < 4^b ? in the Data Sufficiency forum “\ Target question: Is a^5 > 4^b Statement 1: a³ = -27 Solve to get: a = -3 So, a^5 = (-3)^5 = -243 Since 4^b will be POSITIVE for all values of b, the answer to the target question is NO, a^5 is definitely NOT greater than 4^b Since we can answer the target question with certainty, ...” May 7, 2019 Brent@GMATPrepNow posted a reply to Anthony and Michael sit on the six-member board of directors in the Problem Solving forum “Let''s assume that we''re creating subcommittees. We want to place 6 people in the following spaces: _ _ _ | _ _ _ First, we place Michael in one subcommittee; it makes no difference which one: M _ _ | _ _ _ Now place Anthony. We can see that there are 5 spaces remaining. 2 spaces ...” May 7, 2019 Max@Math Revolution posted a new topic called A book has 1000 pages numbered 1, 2, 3, …, and so on. How ma in the Problem Solving forum “[GMAT math practice question] A book has 1000 pages numbered 1, 2, 3, …, and so on. How many times does the digit 2 appear on the page numbers? A. 200 B. 250 C. 300 D. 400 E. 500” May 7, 2019 Max@Math Revolution posted a new topic called If x, y, and z are integers, is xyz a multiple of 6? in the Data Sufficiency forum “[GMAT math practice question] If x, y, and z are integers, is xyz a multiple of 6? 1) x+y+z is a multiple of 6 2) x, y, and z are consecutive” May 7, 2019 Brent@GMATPrepNow posted a reply to If x is 8/3 percent of y, y is what percent of x? in the Problem Solving forum “x percent = x/100 So, 8/3 percent = (8/3)/100 = (8/3)/(100/1) = (8/3)(1/100) = 8/300 GIVEN: x is 8/3 percent of y, We can write: x = 8/300 of y In other words: x = (8/300)(y) or......: x = 8y/300 y is what percent of x? Take: x = 8y/300 Multiply both sides by 300 to get: 300x = 8y ...” May 7, 2019 Max@Math Revolution posted a new topic called What is the remainder when the product of the first 10 prime in the Problem Solving forum “[GMAT math practice question] What is the remainder when the product of the first 10 prime numbers is divided by 4? A. 0 B. 1 C. 2 D. 3 E. not defined” May 6, 2019 Max@Math Revolution posted a new topic called Is x + y < -1? in the Data Sufficiency forum “[GMAT math practice question] Is x + y < -1? 1) |x| > x and |y| > y 2) x^2+y^2 > 1” May 6, 2019 Max@Math Revolution posted a reply to What is the sum of the roots of the equation 4^x – 6·2^x in the Problem Solving forum “=> 4^x – 6·2^x + 8 = 0 => (2^x)^2– 6·2^x + 8 = 0 => (2^x-2)(2^x-4) = 0 => 2^x = 2 or 2^x = 4 => 2^x = 2^1 or 2^x = 2^2 => x = 1 or x = 2 Since 1+2=3, the correct answer is B. Answer: B” May 6, 2019 Max@Math Revolution posted a reply to [x] is the greatest integer less than or equal to x. What is in the Problem Solving forum “=> [√1] = 1 [√2] = 1 [√3] = 1 If 1 ≤ n < 4, then 1 ≤ √n < 2 and [√n] = 1 for n = 1, 2, 3 (3 terms). If 4 ≤ n < 9, then 2 ≤ √n < 3 and [√n] = 2 for n = 4, 5, …, 8 (5(=8-4+1) terms). If 9 ≤ n < 16, then 3 ≤ √n < 4 and [√n] = 3 for n = 9, 10, ...” May 6, 2019 Max@Math Revolution posted a reply to Is the integer n even? 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 ...” May 6, 2019 Max@Math Revolution posted a reply to a, b, c, d and e are real numbers with a < b < c < 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 ...” May 6, 2019 ceilidh.erickson posted a reply to Last year a record number of new manufacturing jobs were in the Critical Reasoning forum “For more on using this strategy for BOLDFACE questions on CR, see: https://www.beatthegmat.com/journalist-every-election-year-at-this-time-the-state-gover-t306075.html https://www.beatthegmat.com/most-of-western-music-since-the-renaissance-has-been-based-t305309.html#823603 ...” May 4, 2019 ceilidh.erickson posted a reply to Last year a record number of new manufacturing jobs were 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 ...” May 4, 2019 ceilidh.erickson posted a reply to Ramón pointed out that food high in whole-grain fiber creat in the Sentence Correction forum “This question is testing SUBJECT-VERB AGREEMENT, modifiers, & logical lists. In the dependent clause "... that food (high in whole grain fiber) creates...", the subject is the singular "food" and the verb is "creates." A. fiber creates the energy we need to ...” May 4, 2019 ceilidh.erickson posted a reply to The outside of the rectangular box represented in the figure in the Problem Solving forum “If we want the minimum amount of wrapping paper, we want to know the SURFACE AREA of all surface except the bottom surface. Calculate each: Top surface area = 25 x 10 = 250 2 sides of 5 x 10 = 2(5*10) = 100 2 sides of 5 x 25 = 2(5*25) = 250 250 + 100 + 250 = 600 The answer is B.” May 4, 2019 ceilidh.erickson posted a reply to On a scale drawing, a rectangle 1 inch by 1 and 1/3 inches in the Problem Solving forum “If the scale is 1 in = 15 ft, then the dimensions of the floor = 15x20 ft. https://i.postimg.cc/4K6VcCdg/Screenshot-2019-05-04-17-44-08.png If each tile is 6 in x 6 in, that''s 1/2 ft x 1/2 ft square. So every 1 sq feet of floor would take 4 tiles. ...” May 4, 2019 ceilidh.erickson posted a reply to In the floor plan of an executive's beach house above in the Problem Solving forum “Let''s set aside the fact that this is an awful floorplan. How would you find furniture to fit this house?! <i class="em em-joy"></i> If the two wall of the living room are parallel, then the kitchen and the (kitchen + living room + bath) are SIMILAR triangles. Similar ...” May 4, 2019 ceilidh.erickson posted a reply to How many integers between 0 and 1570 have a prime tens and in the Problem Solving forum “This is a COMBINATORICS problem. If we''re looking for a prime tens and units digit, we''re counting single-digit prime numbers: 2, 3, 5, and 7. Now we need to count the possibilities for each digit. Since we have the constraint that we''re looking for all #s 0-1570, we have to be careful, ...” May 4, 2019 Brent@GMATPrepNow posted a reply to Last year the range of the annual salaries of the 100 employ 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 ...”
May 4, 2019
Brent@GMATPrepNow posted a reply to Last year the range of the annual salaries of the 100 employ in the Problem Solving forum
“Hey BTGmoderatorDC, You posted this question 2 months ago: https://www.beatthegmat.com/last-year-the-range-of-the-annual-salaries-of-the-100-t306593.html Cheers, Brent”
May 4, 2019
Brent@GMATPrepNow posted a reply to A certain rectangular window is twice as long as it is wide. in the Problem Solving forum
“Approach #2: Algebra Let x = the width of the rectangle So, 2x = the length of the rectangle If the perimeter is 10, we can write: x + x + 2x + 2x = 10 Simplify: 6x = 10 Solve: x = 10/6 = 5/3 So, the width (x) is 5/3 And the length (2x) is 10/3 Answer: B Cheers, Brent”
May 4, 2019
Brent@GMATPrepNow posted a reply to A certain rectangular window is twice as long as it is wide. in the Problem Solving forum
“We COULD use algebra to solve this question. However, it''s probably faster to just test the answer choices The answer choices give us the length and width of the rectangle. So, the sum of two values will equal HALF the perimeter of the rectangle. Since we want a perimeter of 10, the ...”
May 4, 2019
Brent@GMATPrepNow posted a reply to Three-fourths of the area of a rectangular lawn 30 feet wide in the Problem Solving forum
“Here''s a diagram of the 30 x 40 lawn https://i.imgur.com/6dQyyQ5.png If we keep the full width (of 30 feet), then the length of the enclosure = 3/4 of 40 = 30 feet https://i.imgur.com/nRkAVRU.png So, the enclosure is a 30 by 30 square. The PERIMETER = 30 + 30 + 30 + 30 = 120 feet If ...”
May 4, 2019
Brent@GMATPrepNow posted a reply to If rectangle ABCD is inscribed in the circle above, what is in the Problem Solving forum
“Draw a line connecting points A and C. https://i.imgur.com/fQaxM5q.png An important circle property (see video below for more info) tells us that, if we have a 90-degree inscribed angle, then that angle must be containing ("holding") the DIAMETER of the circle. So, we know that AC = ...”
May 4, 2019
Brent@GMATPrepNow posted a reply to In quadrilateral ABCD above, what is the length of AB ? in the Problem Solving forum
“https://i.imgur.com/srEvM6A.png If we focus on the blue right triangle, we can EITHER recognize that legs of length 3 and 4 are part of the 3-4-5 Pythagorean triplet, OR we can apply the Pythagorean Theorem. https://i.imgur.com/L50lEKr.png Either way, we''ll see that the triangle''s ...”
May 4, 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. ...”
May 3, 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. ...”
May 3, 2019
Max@Math Revolution posted a new topic called What is the sum of the roots of the equation 4^x – 6·2^x + 8 in the Problem Solving forum
“[GMAT math practice question] What is the sum of the roots of the equation 4^x – 6·2^x + 8 = 0? A. 1 B. 3 C. 6 D. 8 E. 12”
May 3, 2019
Max@Math Revolution posted a reply to x^2 + 4x + 1 = 0. What is the value of x^2 + 1/x^2? in the Problem Solving forum
“=> x^2 + 4x + 1 = 0 => x + 4 + 1/x = 0 => x + 1/x = -4 So, (x + 1/x)2 = (-4)^2 and x^2 +2x(1/x) + 1/x^2 = 16. Therefore, x^2 +2 + 1/x^2 = 16 and x^2 + 1/x^2 = 14. Therefore, the answer is C. Answer: C ”
May 3, 2019
Max@Math Revolution posted a new topic called Is the integer n even? in the Data Sufficiency forum
“[GMAT math practice question] Is the integer n even? 1) There is a sum of n consecutive integers that is even. 2) [n/2] is an even number, where [n] is the greatest integer less than or equal to n.”
May 3, 2019
Max@Math Revolution posted a reply to In the x-y plane, the graph of y=f(x)=ax^2+bx+c passes throu 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 ...”
May 3, 2019
Max@Math Revolution posted a new topic called [x] is the greatest integer less than or equal to x. What is in the Problem Solving forum
“[GMAT math practice question] [x] is the greatest integer less than or equal to x. What is the value of [√1] + [√2] + [√3] + … + [√49] + [√50]? A. 115 B. 195 C. 217 D. 288 E. 360”
May 3, 2019
Max@Math Revolution posted a reply to 1/1^2 + 1/2^2 + 1/3^2 + 1/4^2 + … = π^2/6. What is the va in the Problem Solving forum
“=> Set x = 1/1^2 + 1/3^2 + 1/5^2 + … . Then π^2/6 =1/1^2 + 1/2^2 + 1/3^2 + 1/4^2 + … = (1/1^2 + 1/3^2 + 1/5^2 + … ) + (1/2^2 + 1/4^2 + 1/6^2 + … ) = (1/1^2 + 1/3^2 + 1/5^2 + … ) + (1/(1*2)^2 + 1/(2*2)^2 + 1/(2*3)^2 + … ) = (1/1^2 + 1/3^2 + 1/5^2 + … ) + (1/4)(1/1)^2 + ...”
May 3, 2019
Brent@GMATPrepNow posted a reply to A paint mixture was formed by mixing exactly 3 colors of in the Data Sufficiency forum
“Target question: How many gallons of green paint were used? Given: A paint mixture was formed by mixing exactly 3 colors of paint. By volume, the mixture was x% blue paint, y% green paint, and z% red paint. 1 gallon of blue paint and 3 gallons of red paint were used. In other words, we ...”
May 2, 2019
Brent@GMATPrepNow posted a reply to If 2.00X and 3.00Y are 2 numbers in decimal form with thousa in the Data Sufficiency forum
“ Given: 2.00X and 3.00Y are 2 numbers in decimal form with thousandths digits X and Y Target question: Is 3(2.00X) > 2(3.00Y)? This is a good candidate for rephrasing the target question. Since X is the thousandths digit, we can write: 2.00X = 2 + X/1000 Since Y is the thousandths ...”
May 2, 2019
Max@Math Revolution posted a new topic called a, b, c, d and e are real numbers with a < b < c < d < e. Is in the Data Sufficiency forum
“[GMAT math practice question] a, b, c, d and e are real numbers with a < b < c < d < e. Is abcde negative? 1) abc < 0 2) cde < 0”
May 2, 2019
Max@Math Revolution posted a reply to What is the volume of a sphere? 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 ...”
May 2, 2019
Brent@GMATPrepNow posted a reply to If n^m leaves a remainder of 1 after division by 7 for all in the Problem Solving forum
“The most important piece of information is here: "for all positive integers n that are not multiples of 7" Since 2 is not a multiple of 7, then it must be the case that, for a particular value of m, 2^m leaves a remainder of 1 after division by 7 Let''s check the answer choices.... ...”
May 1, 2019
Max@Math Revolution posted a new topic called x^2 + 4x + 1 = 0. What is the value of x^2 + 1/x^2? in the Problem Solving forum
“[GMAT math practice question] x^2 + 4x + 1 = 0. What is the value of x^2 + 1/x^2? A. 10 B. 12 C. 14 D. 16 E.18”
May 1, 2019
Max@Math Revolution posted a reply to Alice, Bob, Cindy, Daren, Eddie, Farrell sit on chairs aroun in the Problem Solving forum
“=> https://i.postimg.cc/R3BJ3KtR/429.png First, place Alice and Farrell in opposite chairs as shown above (there is only one way to do this as the table is round). Next, arrange the four remaining people in 4! = 24 ways. Therefore, C is the answer. Answer: C”
May 1, 2019
Max@Math Revolution posted a new topic called In the x-y plane, the graph of y=f(x)=ax^2+bx+c passes throu in the Data Sufficiency forum
“[GMAT math practice question] In the x-y plane, the graph of y=f(x)=ax^2+bx+c passes through (-2,0) and (2,0). Is f(4) < 0? 1) f(0) > 0 2) f(-3) < 0”
May 1, 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 ...”
May 1, 2019
Brent@GMATPrepNow posted a reply to If x is an integer greater than 0, what is the remainder in the Data Sufficiency forum
“Target question: What is the remainder when x is divided by 4 ? Statement 1: The remainder is 3 when x + 1 is divided by 4. ------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 ...”
May 1, 2019
Brent@GMATPrepNow posted a reply to What number is 6 more than x + y ? in the Data Sufficiency forum
“Target question: What is the value of x + y + 6? Statement 1: y is 3 less than x. We can write: y = x - 3 There are several values of x and y that satisfy this equation. Here are two: Case a: x = 3 and y = 0. In this case, the answer to the target question is x + y + 6 = 3 + 0 + 6 = 9 ...”
May 1, 2019
Brent@GMATPrepNow posted a reply to Is the average (arithmetic mean) of the numbers x, y, and z in the Data Sufficiency forum
“Target question: Is the average (arithmetic mean) of the numbers x, y, and z greater than z? This is a good candidate for rephrasing the target question. Rewrite the question as "Is (x + y + z)/3 > z?" Multiply both sides by 3 to get: "Is x + y + z > 3z?" Subtract z ...”
May 1, 2019
Brent@GMATPrepNow posted a reply to Every object in a box is either a sphere or a cube, and ever in the Data Sufficiency forum
“Target question: How many objects are in the box? Given: Every object in a box is either a sphere or a cube, and every object in the box is either red or green. We can solve this using the Double Matrix Method. This technique can be used for most questions featuring a population in which ...”
May 1, 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 5 ? Statement 1: When n is divided by 3, the quotient is 4 and the remainder is 1. 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 ...”
April 30, 2019
Brent@GMATPrepNow posted a reply to Is n equal to zero? in the Data Sufficiency forum
“Target question: Is n equal to zero? Statement 1: The product of n and some nonzero number is 0 (n)(non-zero number) = 0 This means n must be 0 Since we can answer the target question with certainty, statement 1 is SUFFICIENT Statement 2: The sum of n and 0 is 0 If n + 0 = 0, we can ...”
April 30, 2019
Brent@GMATPrepNow posted a reply to If r and s are positive numbers and θ is one in the Data Sufficiency forum
“ Given: r and s are positive numbers and θ is one of the operations, +, −, ×, or ÷ Target question: Which operation is θ ? Statement 1: If r = s, then r θ s = 0 Keep in mind that r and s are POSITIVE So, we have POSITIVE θ POSITIVE = 0 POSITIVE + POSITIVE ≠ 0 So, θ cannot ...”
April 30, 2019
Brent@GMATPrepNow posted a reply to How many hours does it take Jennifer to run y miles if she r in the Problem Solving forum
“time = distance/rate So, time = y/x Answer: B Cheers, Brent”
April 30, 2019
Brent@GMATPrepNow posted a reply to If x = 5 – 4k and y = 5k – 3, then for what value of k d in the Problem Solving forum
“We want: x = y Replace values with their equivalents: 5 - 4k = 5k - 3 Add 4k to both sides: 5 = 9k - 3 Add 3 to both sides: 8 = 9k Divide both sides by 9 to get: 8/9 = k Answer: B Cheers, Brent”
April 30, 2019