8

Set 3: Circles (Beginner)

Explanation

Answer: D

PROBLEM

A circle has diameter 18. What is its radius?

A circle has diameter 18. What is its radius?

A.

7

B.

8

C.

11

D.

9

✓ Correct

Detailed Explanation

Choice D is the best answer. Radius = Diameter / 2 = 18 / 2 = 9

Why others are wrong:
A: 7 is incorrect because it does not satisfy the equation.
B: 8 is incorrect because it does not satisfy the equation.
C: 11 is incorrect because it does not satisfy the equation.