Official Guide Explanation:
Problem Solving #46




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Solution and Metadata

Question: 46
Page: 158
Difficulty: 4 (Moderately Easy)
Category 1: Arithmetic > Powers and Roots of Numbers > Powers
Category 2: Arithmetic > Fractions >
Category 3: Arithmetic > Decimals >

Explanation: Exponent rules are crucial on problems like this. When the same number is raised to different exponents in the numerator and denominator of a fraction, subtract the exponents. Here, it looks like this: (((0.3)5)/((0.3)3)) = (0.3)(5 - 3) = (0.3)2 = 0.09, choice (C). If you find multiplying decimals particularly error - prone, you can always switch to fractions at the second to last step: (0.3)2 = ( (3/10))2 = (9/100) = 0.09.

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