alanforde800Maximus wrote:What is the median of set A {-8, 15, -9, 4, N}?
1) N is a prime and N� is even
2) 2N + 14 < 20
Please assist with above problem.
Target question: What is the median of set A
Given: set A {-8, 15, -9, 4, N}
Statement 1: N is a prime and N� is even
- If N is even, then N� is even
- If N is odd, then N� is odd
Since we're told that N� is even, we can conclude that N is EVEN, which means N = 2 (since 2 is the only even prime)
Once we know N = 2, set A becomes {-8, 15, -9, 4,
2}, in which case,
the median of set A is 2
Since we can answer the
target question with certainty, statement 1 is SUFFICIENT
Statement 2: 2N + 14 < 20
Subtract 14 from both sides of the inequality to get; 2N < 6
Divide both sides by 2 to get: N < 3
There are several values of N that satisfy statement 2. Here are two:
Case a: N =
2, in which case set A becomes {-8, 15, -9, 4,
2}. In this case,
the median of set A is 2
Case b: N =
-10, in which case set A becomes {-8, 15, -9, 4,
-10}. In this case,
the median of set A is -8
Since we cannot answer the
target question with certainty, statement 2 is NOT SUFFICIENT
Answer =
A
Related video:
https://www.gmatprepnow.com/module/gmat ... /video/800
Cheers,
Brent
