Official Guide Explanation:
Problem Solving #37

Background

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Solution and Metadata

Question: 37
Page: 66
Difficulty: 4 (Moderately Easy)
Category 1: Word Problems > Rate Problems > other
Category 2: Arithmetic > Ratio and Proportion >

Explanation: To get the maximum mileage on 15 gallons of gasoline, the car needs to get its best mileage, 22.4 miles per gallon. To solve for the number of miles, set up a miles per gallon ratio: 22.4 = ((x)/15). To solve: x = 15(22.4). The question asks you to approximate, so do so: start with 15(20) = 300, then 15(2) = 30, so 15(22.4) must be at least 330, and only choice (A) is greater, so it must be correct.

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