Official Guide Explanation:
Problem Solving #114

Background

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Solution and Metadata

Question: 114
Page: 168
Difficulty: 5 (Moderate)
Category 1: Arithmetic > Powers and Roots of Numbers > Powers
Category 2: Arithmetic > Decimals >
Category 3: Arithmetic > Real Numbers >

Explanation: While it wouldn't take long to calculate a² and a³ for a= - 0.3, it's not necessary. There are a few facts you do need to recognize, though. First, if a is negative, a² is positive and a³ is negative. Second, since a is a negative decimal, a³ is greater than a; when decimals are multiplied by themselves, they get closer to zero. So, taking all that information together, a < a³ < a², choice (B).

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