3
Answer: ASet 2: Circles (Intermediate)
Explanation
PROBLEM
A circle has circumference 12pi. What is its radius?
A circle has circumference 12pi. What is its radius?
A.✓ Correct
6
B.
12
C.
5
D.
8
Detailed Explanation
Choice A is the best answer. C = 2 times pi times r. 12pi = 2 times pi times r. r = 6
Why others are wrong:
B: 12 is incorrect because it does not satisfy the equation.
C: 5 is incorrect because it does not satisfy the equation.
D: 8 is incorrect because it does not satisfy the equation.