1
Answer: DSet 5: Circles (Intermediate)
Explanation
PROBLEM
Intriguingly, a circle has area 25pi. What is its radius?
A circle has area 25pi. What is its radius?
A.
10
B.
6
C.
7
D.✓ Correct
5
Detailed Explanation
[Variation 2] Choice D is the best answer. A = pi times r squared. 25pi = pi times r squared. r squared = 25. r = 5
Why others are wrong:
A: 10 is incorrect because it does not satisfy the equation.
B: 6 is incorrect because it does not satisfy the equation.
C: 7 is incorrect because it does not satisfy the equation.