Official Guide Explanation:
Data Sufficiency #81




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Solution and Metadata

Question: 81
Page: 158
Difficulty: 5 (Moderate)
Category 1: Arithmetic > Powers and Roots of Numbers >
Category 2: Algebra > Exponents >

Explanation: x2 is greater than x for any value of x that is not between 0 and 1. (For a more detailed explanation of that, see the explanation for question \#73, above.)

Statement (1) is sufficient: if x2 is greater than 1, x cannot be between 0 and 1, so x2 must be greater than x. Statement (2) is not sufficient: x could be between 0 and 1 (in which case x is greater than x2) or it could be less than 0 or greater than 1 (in which case x2 is greater than x). Choice (A) is correct.

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