Official Guide Explanation:
Problem Solving #97




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Solution and Metadata

Question: 97
Page: 74
Difficulty: 5 (Moderate)
Category 1: Arithmetic > Decimals >
Category 2: Arithmetic > Powers and Roots of Numbers > Roots
Category 3: Arithmetic > Fractions >

Explanation: When the GMAT tells you to approximate, approximate! 5.98 is about 6, 601.5 is about 600, and 15.79 is about 16. With that in mind, rewrite the expression:

rt[((6(600))/16)]= rt[(3600/16)] = (( rt[3600])/( rt[16])) = (60/4) = 15, choice (B).

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