Official Guide Explanation:
Problem Solving #141




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Solution and Metadata

Question: 141
Page: 80
Difficulty: 6 (Moderately Difficult)
Category 1: Geometry > Quadrilaterals >
Category 2: Geometry > Circles > other

Explanation: If the square poster has sides of 2 feet, the area of the poster is s2 = (2)2 = 4. If the area of the circular region is half that, it's (4/2) = 2. The area of a circle is given by π r2, so to find the radius of the circular region, solve the following:

π r2 = 2

r2 = (2/( π ))

r= rt[(2/( π ))], choice (B).

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