Difficulty: Easy
Correct Answer: 38.5
Explanation:
Introduction / Context:Again convert circumference to radius using C = 2 * pi * r, then area A = pi * r^2. This case is tailored to the exact fraction pi = 22/7.
Given Data / Assumptions:
Concept / Approach:Isolate r, then square to compute area.
Step-by-Step Solution:
r = 22 / (2 * 22/7) = 22 * 7 / 44 = 3.5 cmA = pi * r^2 = (22/7) * (3.5)^2 = (22/7) * 12.25 = 22 * 1.75 = 38.5 cm^2Verification / Alternative check:C back = 2*pi*r = 2*(22/7)*3.5 = 22 cm.
Why Other Options Are Wrong:They come from mis-squaring 3.5 or misplacing the 1/7 factor.
Final Answer:38.5
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