BREAKING: Target Test Prep releases Brand New 2026 On Demand GMAT prep course

Redeem

n = ?

This topic has expert replies
Post new topic Post Reply
Previous Topic Next Topic
Source: — Data Sufficiency |
User avatar
GMAT Instructor
Posts: 1248
Joined: Thu Mar 29, 2012 2:57 pm
Location: Everywhere
Thanked: 503 times
Followed by:192 members
GMAT Score:780

by Bill@VeritasPrep » Tue May 01, 2012 6:42 pm
1) n(n+2) = 15

If n=3, n+2=5. 3*5 = 15. If n=-5, n+2=-3. -3*-5 = 15. Insufficient

2) (n+2)^n = 125

125=5^3, which means that n=3. (3+2)^3=5^3=125. Sufficient
Join Veritas Prep's 2010 Instructor of the Year, Matt Douglas for GMATT Mondays

Visit the Veritas Prep Blog

Try the FREE Veritas Prep Practice Test
Top
User avatar
GMAT Instructor
Posts: 3835
Joined: Fri Apr 02, 2010 10:00 pm
Location: Milpitas, CA
Thanked: 1854 times
Followed by:523 members
GMAT Score:770

by Anurag@Gurome » Tue May 01, 2012 10:43 pm
amp0201 wrote:Q. What is the value of the integer n? (1) n(n + 2) = 15 (2) (n + 2)^n = 125
(1) n(n + 2) = 15
n² + 2n = 15
n² + 2n - 15 = 0
n² + 5n - 3n - 15 = 0
n(n + 5) - 3(n + 5) = 0
(n - 3)(n + 5) = 0
n = 3, -5
Two integer values of n, no definite answer; NOT sufficient.

(2) (n + 2)^n = 125
(n + 2)^n = 5^3
n = 3; SUFFICIENT.

The correct answer is B.
Anurag Mairal, Ph.D., MBA
GMAT Expert, Admissions and Career Guidance
Gurome, Inc.
1-800-566-4043 (USA)

Join Our Facebook Groups
GMAT with Gurome
https://www.facebook.com/groups/272466352793633/
Admissions with Gurome
https://www.facebook.com/groups/461459690536574/
Career Advising with Gurome
https://www.facebook.com/groups/360435787349781/
Top
Post new topic Post Reply
• Page 1 of 1