ardz24 wrote:What is the value of (k - w ) + (k - x ) + (k - y )?
(1) w, x, and y are three consecutive odd numbers
(2) The mean of w, x, and y is k
Target question: What is the value of (k - w ) + (k - x ) + (k - y )?
This is a good candidate for
rephrasing the target question.
Take:
(k - w ) + (k - x ) + (k - y )
Simplify to get:
3k - w - x - y
Rewrite as:
3k - (w + x + y)
REPHRASED target question: What is the value of 3k - (w + x + y) ?
Aside: Here's a video with tips on rephrasing the target question: https://www.gmatprepnow.com/module/gmat- ... cy?id=1100
Statement 1: w, x, and y are three consecutive odd numbers
Since we have no information about k, there's no way to determine the value of
3k - (w + x + y)
Since we cannot answer the
REPHRASED target question with certainty, statement 1 is NOT SUFFICIENT
Statement 2: The mean of w, x, and y is k
This tells us that (w + x + y)/3 = k
Multiply both sides by 3 to get: w + x + y = 3k
If w + x + y =
3k, then
3k - (w + x + y) = 3k - (
3k) =
0
Perfect, the answer to the
REPHRASED target question is
0
Since we can answer the
REPHRASED target question with certainty, statement 2 is SUFFICIENT
Answer: B
Cheers,
Brent
