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100 points for $49 worth of Veritas practice GMATs FREE VERITAS PRACTICE GMAT EXAMS Earn 10 Points Per Post Earn 10 Points Per Thanks Earn 10 Points Per Upvote ## If x is a positive even integer, and n and m... tagged by: swerve ##### This topic has 4 expert replies and 1 member reply ### Top Member ## If x is a positive even integer, and n and m... If x is a positive even integer, and n and m are cosecutive integers, then $$\frac{\left(n-m\right)^x}{\left(m-n\right)^x}=?$$ A. -2 B. -1 C. 0 D. 1 E. 2 The OA is D. Please, can any expert explain this PS question for me? I tried to solve it but I can't get the correct answer. I need your help. Thanks. ### GMAT/MBA Expert Elite Legendary Member Joined 23 Jun 2013 Posted: 10197 messages Followed by: 496 members Upvotes: 2867 GMAT Score: 800 Top Reply Hi swerve, We're told that X is a positive EVEN integer, and N and M are CONSECUTIVE integers. We're asked to find the value of [(N - M)^X] / ([M - N)^X]. This question can be solved by TESTing VALUES. IF... X = 2, N = 2 and M=3.... (2-3)^2 = (-1)^2 = +1 (3-2)^2 = (1)^2 = +1 +1/+1 = +1 Final Answer: D GMAT assassins aren't born, they're made, Rich _________________ Contact Rich at Rich.C@empowergmat.com ### GMAT/MBA Expert Legendary Member Joined 14 Jan 2015 Posted: 2667 messages Followed by: 122 members Upvotes: 1153 GMAT Score: 770 Top Reply swerve wrote: If x is a positive even integer, and n and m are cosecutive integers, then $$\frac{\left(n-m\right)^x}{\left(m-n\right)^x}=?$$ A. -2 B. -1 C. 0 D. 1 E. 2 The OA is D. Please, can any expert explain this PS question for me? I tried to solve it but I can't get the correct answer. I need your help. Thanks. You can also use some simple number properties. Because we're raising both expressions to an even exponent, we know both numerator and denominator must be non-negative. We also know that the difference of two consecutive numbers will always be 1 or -1. If they can't be negative, we know both values must equal 1. _________________ Veritas Prep | GMAT Instructor Veritas Prep Reviews Save$100 off any live Veritas Prep GMAT Course

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swerve wrote:
If x is a positive even integer, and n and m are cosecutive integers, then
$$\frac{\left(n-m\right)^x}{\left(m-n\right)^x}=?$$
A. -2
B. -1
C. 0
D. 1
E. 2

The OA is D.

Please, can any expert explain this PS question for me? I tried to solve it but I can't get the correct answer. I need your help. Thanks.
Pick easy numbers. Say x = 2, n = 4 and m = 3.
We want (4-3)^2 /(3-4)^2 = 1^2 / (-1)^2 = 1/1 = 1. The answer is D

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Save $100 off any live Veritas Prep GMAT Course Enroll in a Veritas Prep GMAT class completely for FREE. Wondering if a GMAT course is right for you? Attend the first class session of an actual GMAT course, either in-person or live online, and see for yourself why so many students choose to work with Veritas Prep. Find a class now! Senior | Next Rank: 100 Posts Joined 15 Jan 2018 Posted: 83 messages The difference between consecutive integers is 1 or -1. Raising to an even power will always produce 1 (because -1 x -1 = 1). And 1/1 = 1 So answer = 1. ### GMAT/MBA Expert GMAT Instructor Joined 25 Apr 2015 Posted: 2791 messages Followed by: 18 members Upvotes: 43 swerve wrote: If x is a positive even integer, and n and m are cosecutive integers, then $$\frac{\left(n-m\right)^x}{\left(m-n\right)^x}=?$$ A. -2 B. -1 C. 0 D. 1 E. 2 Notice that (n - m)^x / (m - n)^x = [(n - m)/(m - n)]^x = (-1)^x Since x is a positive even integer, (-1)^x will always be equal to 1. Alternate solution: Letâ€™s use some strategic numbers for n, m, and x. n = 4, m = 3, and x = 2, thus: [(4 - 3)^2]/(3 - 4)^2 = 1^2/(-1)^2 = 1 Answer: D _________________ Scott Woodbury-Stewart Founder and CEO scott@targettestprep.com See why Target Test Prep is rated 5 out of 5 stars on BEAT the GMAT. Read our reviews • Magoosh Study with Magoosh GMAT prep Available with Beat the GMAT members only code • 5-Day Free Trial 5-day free, full-access trial TTP Quant Available with Beat the GMAT members only code • Free Practice Test & Review How would you score if you took the GMAT Available with Beat the GMAT members only code • Free Veritas GMAT Class Experience Lesson 1 Live Free Available with Beat the GMAT members only code • Award-winning private GMAT tutoring Register now and save up to$200

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