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rishianand7
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Target question: Is x^3 > y?rishianand7 wrote:If x and y are positive, is x^3 > y?
(1) x^(1/2) > y
(2) x > y
Statement 1: x^(1/2) > y
Aside: x^(1/2) = √x
There are several values of x and y that satisfy this condition. Here are two:
Case a: x = 1/4 and y = 1/5 (since 1/4^(1/2) = 1/2, and 1/2 is greater than 1/5). In this case x^3 is less than y
Case b: x = 4 and y = 1 (since 4^(1/2) = 2, and 2 is greater than 1). In this case x^3 is greater than y
Since we cannot answer the target question with certainty, statement 1 is NOT SUFFICIENT
Statement 2: x > y
There are several values of x and y that satisfy this condition. Here are two:
Case a: x = 1/4 and y = 1/5. In this case x^3 is less than y
Case b: x = 4 and y = 1. In this case x^3 is greater than y
Since we cannot answer the target question with certainty, statement 2 is NOT SUFFICIENT
Statements 1 and 2 combined
Notice that I used the same values for x and y for both statements. So, if those values yielded NOT SUFFICIENT conclusions for each statement alone, they will yield a NOT SUFFICIENT conclusion for the statement combined.
Answer = E
Cheers,
Brent
