8

Set 1: Circles (Intermediate)

Explanation

Answer: B

PROBLEM

A circle has radius 6. What is the arc length of a 120-degree sector? (Express as a number times pi)

A circle has radius 6. What is the arc length of a 120-degree sector? (Express as a number times pi)

A.

6pi

B.

4pi

✓ Correct
C.

5pi

D.

12pi

Detailed Explanation

Choice B is the best answer. Arc length = (120/360) times 2 times pi times 6 = 4pi

Why others are wrong:
A: 6pi is incorrect because it does not satisfy the equation.
C: 5pi is incorrect because it does not satisfy the equation.
D: 12pi is incorrect because it does not satisfy the equation.