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ashish1354
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both stems suggest that x<1.
OA : D
inequality problem help needed.
This topic has expert replies
Source: Beat The GMAT — Data Sufficiency |
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bluementor
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Statement 1:ashish1354 wrote:31. Is X greater than 1?
(1) X > X^2.
(2) –X < -X^2
x > x^2
x^2 - x < 0
x(x-1) < 0
Either x or (x-1) must be less than 0, and the other must be positive. Clearly x must be positive since its larger than (x-1). The only possible range for x is therefore 0<x<1, which answers the question stem a definite NO. Sufficient.
Statement 2:
-x < -x^2
x^2 -x < 0
x(x-1)<0
Same conclusion can be drawn here as it is done in statement 1. Sufficient.
Choose D.
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Stuart@KaplanGMAT
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Bluementor's solution is great - just a quick guessing point.ashish1354 wrote:31. Is X greater than 1?
(1) X > X^2.
(2) –X < -X^2
We can multiply both sides of the inequality in (2) to turn it into the inequality in (1); in other words the two statements are identical.
When you have identical statements, we can always eliminate (A), (B) and (C) - so even if we have no clue whether the information is sufficient, we still have a 50/50 shot at the question.
Stuart Kovinsky | Kaplan GMAT Faculty | Toronto
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