Official Guide Explanation:
Problem Solving #27




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Solution and Metadata

Question: 27
Page: 65
Difficulty: 4 (Moderately Easy)
Category 1: Arithmetic > Fractions >
Category 2: Arithmetic > Decimals >

Explanation: The easiest way to complete this problem and avoid careless mistakes by miscounting zeroes is to give all the fractions a common denominator. Multiply the first by 1,000 and the second by 100: ((3,000)/(100,000)) + (500/(100,000)) + (7/(100,000)) = ((3,507)/(100,000)). To find the decimal equivalent, see how many places the decimal in the denominator has to move to turn into 1. Since you have to move the decimal five places, you must do the same in the numerator: ((3,507)/(100,000)) = ((.03507)/1) = 0.03507, choice (E).

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