carcass wrote:
Is x > y ?
(1) x + y > x − y
(2) 3x > 2y
(DS04468)
Target question: Is x > y ? Statement 1: x + y > x − y Add y to both sides of the inequality to get: x + 2y > x
Subtract x from both sides: 2y > 0
But this tells us that
y is positive However, since we're provided no information about the value of x, statement 1 is NOT SUFFICIENT
Statement 2: 3x > 2yThere are several values of x and y that satisfy statement 2. Here are two:
Case a: y = 2 and y = 1. In this case, the answer to the target question is
YES, x is greater than yCase b: y = 2 and y = 2. In this case, the answer to the target question is
NO, x is not greater than ySince we can’t answer the
target question with certainty, statement 2 is NOT SUFFICIENT
Statements 1 and 2 combined Statement 1 indirectly tells us that
y is positive Statement 2 tells us that 3x > 2y
Strategy tip: It's hard to tell whether the combined statements are sufficient. This is a good time to see if we can
reuse the values we used earlier with statement 2.
It turns out that the counterexamples we used for statement 2 also satisfy statement 1. That is...
Case a: y = 2 and y = 1. In this case, the answer to the target question is
YES, x is greater than yCase b: y = 2 and y = 2. In this case, the answer to the target question is
NO, x is not greater than ySince we can’t answer the
target question with certainty, the combined statements are NOT SUFFICIENT
Answer: E
Cheers,
Brent
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Brent Hanneson – Creator of gmatprepnow.com
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