A circle has a circumference of 10 pi. What is its area?
Answer and explanation
Correct answer: C. 25 pi
- Step 1: The circumference is 2 pi r, so 2 pi r = 10 pi and r = 5. Step 2. The area is pi r squared = 25 pi. Answer: 25 pi. Why not the others: 10 pi is the circumference, and 50 pi and 100 pi come from using the wrong radius.
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