A circle has radius 10 cm. What is its area in terms of pi?
Answer and explanation
Correct answer: A. 100pi
- Step 1: The area of a circle is pi times the radius squared.
- Step 2: A = pi x 10^2 = 100 pi.
Answer
100pi.
Why not the others: 20pi is the circumference; 10pi forgets to square the radius; 200pi doubles the correct area.
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