Official Guide Explanation:
Problem Solving #4




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Solution and Metadata

Question: 4
Page: 62
Difficulty: 4 (Moderately Easy)
Category 1: Arithmetic > Powers and Roots of Numbers > Powers
Category 2: Algebra > Exponents >

Explanation: When you see a quantity multiplied by something like 10k, you know you'll be working with scientific notation. If you move the decimal point enough places, you can turn 0.0010101 into 1,010.1, a number just a little bit bigger than 1,000. To figure out the exact relationship between 0.0010101 and 1,010.1, count the number of places you moved the decimal point: in this case, it's 6. Thus, 1,010.1 = 0.0010101 * 106. If the exponent were smaller than 6, the number would be less than 1,000, so k = 6.

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