BTGModeratorVI wrote: ↑Fri May 29, 2020 6:32 am
If k is an integer, is k even?
(1) k > 1
(2) k^2 is an even integer.
Answer:
B
Source: GMAT prep
Given: k is an integer
Target question: k even?
Statement 1: k > 1
There are infinitely many values of k that satisfy statement 1. Here are two:
Case a: k = 2. In this case, the answer to the target question is
YES, k is even
Case b: k = 3. In this case, the answer to the target question is
NO, k is not even
Since we cannot answer the
target question with certainty, statement 1 is NOT SUFFICIENT
Statement 2: k^2 is an even integer.
In other words,
(k)(k) is even
Since k is an INTEGER, we know that k must be ODD or EVEN
Let's examine each case:
Case a: k is odd. In this case, we get:
(ODD)(ODD) is even. This doesn't work.
So, it CANNOT be the case that k is odd.
Case b: k is even. In this case, we get:
(EVEN)(EVEN) is even.
This works.
So
it must be the case that k is even
Since we can answer the
target question with certainty, statement 2 is SUFFICIENT
Answer: B
Cheers,
Brent
