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

Redeem

n = ?

Expert replies
Source: — Data Sufficiency |

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
Join the discussion

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/
Join the discussion