Official Guide Explanation:
Problem Solving #143

 

 

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: 143
Page: 80
Difficulty: 5 (Moderate)
Category 1: Word Problems > Mixture Problems >
Category 2: Arithmetic > Percents > other

Explanation: The total of the investments is $500 + $1,500 = $2,000. An 8.5 percent return on $2,000 is $2,000(0.085) = $170. A 7 percent return on $500 is $500(0.07) = $35, so the return on the $1,500 investment must be $170 - $35 = $135. To find the percent return on the $1,500 investment, set up an equation:

$135 = $1500(x)

x = (135/1500) = (27/300) = (9/100) = 9%, choice (A).

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