9
Answer: ASet 1: Circles (Intermediate)
Explanation
PROBLEM
A circle has circumference 14pi. What is its radius?
A circle has circumference 14pi. What is its radius?
A.✓ Correct
7
B.
9
C.
6
D.
5
Detailed Explanation
Choice A is the best answer. C = 2 times pi times r. 14pi = 2 times pi times r. r = 7
Why others are wrong:
B: 9 is incorrect because it does not satisfy the equation.
C: 6 is incorrect because it does not satisfy the equation.
D: 5 is incorrect because it does not satisfy the equation.