Set 2: Circles (Advanced)

**Choice D is the best answer.** Arc = (angle/360) times 2 times pi times r. 3.333333333333333pi = (angle/360) times 10pi. angle = 120 degrees

Explanation

Answer: D

PROBLEM

A circle has radius 5 and an arc length of 3.333333333333333pi. What is the central angle in degrees?

122

119

120

✓ Correct

Detailed Explanation

Choice D is the best answer. Arc = (angle/360) times 2 times pi times r. 3.333333333333333pi = (angle/360) times 10pi. angle = 120 degrees

Why others are wrong:

A: 122 is incorrect because it does not satisfy the equation.

B: 60 is incorrect because it does not satisfy the equation.

C: 119 is incorrect because it does not satisfy the equation.