Is w greater than 1?
1. w+2 > 0
2. w^2 > 1
My approach:
1. w+2 >0 then w> -2 Not sufficient
2. w^2 > 1 then w >1 or w < -1. Not sufficient
Combining 1 & 2, we get -2 < w < -1 and hence w < 1. My answer : C
But OA is E. Can anyone explain?[/b]
Can anyone help me with this GMATPrep DS question?
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Yeah ... I did realize it but after posting and thinking for a minute...Anyways thanks for the input
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If you have a feeling that a statement is not sufficient, you can look for contradictory cases.abhijeet_g wrote:Is w greater than 1?
1. w+2 > 0
2. w^2 > 1
Target question: Is w greater than 1?
Statement 1: w+2 > 0
There are several values of w that meet this condition. Here are two:
Case a: w = 2, in which case w is greater than 1
Case b: w = -1.5, in which case w is not greater than 1
Since we cannot answer the target question with certainty, statement 1 is NOT SUFFICIENT
Statement 2: w^2 > 1
There are several values of w that meet this condition. Here are two:
Case a: w = 2, in which case w is greater than 1
Case b: w = -1.5, in which case w is not greater than 1
Since we cannot answer the target question with certainty, statement 2 is NOT SUFFICIENT
Statements 1 and 2 combined:
There are several values of w that meet both conditions. Here are two:
Case a: w = 2, in which case w is greater than 1
Case b: w = -1.5, in which case w is not greater than 1
Since we cannot answer the target question with certainty, the combined statements are NOT SUFFICIENT
Answer = E
Cheers,
Brent