Official Guide Explanation:
Data Sufficiency #68

 

 

Background

This is just one of hundreds of free explanations I've created to the quantitative questions in The Official Guide for GMAT Quantitative Review (2nd ed.). Click the links on the question number, difficulty level, and categories to find explanations for other problems.

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Solution and Metadata

Question: 68
Page: 157
Difficulty: 5 (Moderate)
Category 1: Algebra > Inequalities > other
Category 2: Arithmetic > Fractions >
Category 3: Arithmetic > Real Numbers >

Explanation: Statement (1) is insufficient: if x and y are both positive, the product xy can be no greater than 3(2) = 6, but if they are both negative, the result could be greater than 6; for example, if x= - 4 and y= - 3, xy = (-4)(-3) = 12. Statement (2) is sufficient: the largest xy could be is a little bit less than ((2/3))(8) = 5(1/3). y could be negative, as in (1), but since x cannot be negative, there is no large positive outcome possible. Choice (B) is correct.

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