Official Guide Explanation:
Problem Solving #143




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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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