Official Guide Explanation:
Problem Solving #20




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Solution and Metadata

Question: 20
Page: 155
Difficulty: 3 (Very Easy)
Category 1: Arithmetic > Fractions >
Category 2: Arithmetic > Ratio and Proportion >

Explanation: To simplify a ratio, you can manipulate one side any way you like as long as you do the same to the other side. (Ratios are fractions, so you can treat them the same way.) Since all of the answer choices contain integers, you'll want to change (1/3) into an integer. Thus, multiply both sides of 2:(1/3) by 3: 2(3):3((1/3)) = 6:1, choice (A).

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