Max@Math Revolution wrote:[Math Revolution GMAT math practice question]
What is the value of (2^p)/(2^q) ?
1) p = q + 2
2) pq = 8
Target question: What is the value of (2^p)/(2^q) ?
This is a good candidate for
rephrasing the target question.
Aside: Here's a video with tips on rephrasing the target question: https://www.gmatprepnow.com/module/gmat- ... cy?id=1100
Take:
(2^p)/(2^q)
Apply the Quotient law to get:
2^(p - q)
This means
(2^p)/(2^q) =
2^(p - q)
So, in order to evaluate
(2^p)/(2^q), all we need to do is determine the value of p - q
So,......
REPHRASED target question: What is the value of p-q ?
Statement 1: p = q + 2
Subtract q from both sides to get:
p - q = 2
So, the answer to the target question is
p - q = 2
Since we can answer the
REPHRASED target question with certainty, statement 1 is SUFFICIENT
Statement 2: pq = 8
There are several values of x and y that satisfy statement 2. Here are two:
Case a: p = 8 and q = 1. In this case, the answer to the REPHRASED target question is
p - q = 7
Case b: p = 4 and q = 2. In this case, the answer to the REPHRASED target question is
p - q = 2
Since we cannot answer the
REPHRASED target question with certainty, statement 2 is NOT SUFFICIENT
Answer: A
Cheers,
Brent
Brent Hanneson - Creator of GMATPrepNow.com
