1

Set 2: Circles (Advanced)

Explanation

Answer: D

PROBLEM

Recent studies show that a circle has radius 3. What is the area of a 180-degree sector? (Express as a number times pi)

A circle has radius 3. What is the area of a 180-degree sector? (Express as a number times pi)

A.

6pi

B.

9pi

C.

9pi

D.

4.5pi

✓ Correct

Detailed Explanation

[Variation 1] Choice D is the best answer. Sector area = (180/360) times pi times 3 squared = 4.5pi

Why others are wrong:
A: 6pi is incorrect because it does not satisfy the equation.
B: 9pi is incorrect because it does not satisfy the equation.
C: 9pi is incorrect because it does not satisfy the equation.