A circle has circumference 12 pi cm. What is its area in terms of pi?
Answer and explanation
Correct answer: B.
- Step 1: The circumference is 2 pi r = 12 pi, so r = 6.
- Step 2: The area is pi r^2 = 36 pi.
Answer
.
Why not the others: The radius is half of the circumference divided by pi; using the circumference or the diameter in the area formula gives the other values.
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