Official Guide Explanation:
Data Sufficiency #25

 

 

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: 25
Page: 154
Difficulty: 4 (Moderately Easy)
Category 1: Algebra > Linear Equations-Two Unk >
Category 2: Algebra > Exponents >

Explanation: Statement (1) is insufficient: there are a few different pairs of integers whose product is 27. Statement (2) is also insufficient: any pair of numbers where one is the square of the other would fulfill this requirement.

Taken together, the statements are sufficient. If xy = 27 and x = y2, then:

(y2)(y) = 27

y3 = 27

y = 3

Choice (C) is correct.

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