7
Answer: CSet 1: Circles (Beginner)
Explanation
PROBLEM
A circle has radius 5. What is its circumference? (Express answer as a number times pi)
A circle has radius 5. What is its circumference? (Express answer as a number times pi)
A.
25pi
B.
12pi
C.✓ Correct
10pi
D.
5pi
Detailed Explanation
Choice C is the best answer. Circumference = 2 times pi times r = 2 times pi times 5 = 10pi
Why others are wrong:
A: 25pi is incorrect because it does not satisfy the equation.
B: 12pi is incorrect because it does not satisfy the equation.
D: 5pi is incorrect because it does not satisfy the equation.