Set 3: Circles (Advanced)

[Variation 1] **Choice C is the best answer.** Arc length = (90/360) times 2 times pi times 7 = 3.5pi

Explanation

Answer: C

PROBLEM

Recent studies show that a circle has radius 7. What is the arc length of a 90-degree sector? (Express as a number times pi)

A circle has radius 7. What is the arc length of a 90-degree sector? (Express as a number times pi)

7pi

14pi

3.5pi

✓ Correct

4.5pi

Detailed Explanation

[Variation 1] Choice C is the best answer. Arc length = (90/360) times 2 times pi times 7 = 3.5pi

Why others are wrong:

A: 7pi is incorrect because it does not satisfy the equation.

B: 14pi is incorrect because it does not satisfy the equation.

D: 4.5pi is incorrect because it does not satisfy the equation.