1
Answer: BSet 4: Circles (Intermediate)
Explanation
PROBLEM
A circle has area 16pi. What is its radius?
A circle has area 16pi. What is its radius?
A.
8
B.✓ Correct
4
C.
5
D.
2
Detailed Explanation
Choice B is the best answer. A = pi times r squared. 16pi = pi times r squared. r squared = 16. r = 4
Why others are wrong:
A: 8 is incorrect because it does not satisfy the equation.
C: 5 is incorrect because it does not satisfy the equation.
D: 2 is incorrect because it does not satisfy the equation.