Civil Service Exam Reviewer · Measurement and Geometry · hard
A circle has an area of 78.5 m². What is its circumference? (π = 3.14)
- 31.4 m
- 15.7 m
- 39.25 m
- 62.8 m
Answer
A. 31.4 m
Solution
r² = 78.5 ÷ 3.14 = 25 → r = 5. C = 2πr = 31.4 m.
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