Set 4: Circles (Beginner)

[Variation 1] **Choice D is the best answer.** Circumference = 2 times pi times r = 2 times pi times 4 = 8pi

Explanation

Answer: D

PROBLEM

Recent studies show that a circle has radius 4. What is its circumference? (Express answer as a number times pi)

A circle has radius 4. What is its circumference? (Express answer as a number times pi)

10pi

4pi

16pi

8pi

✓ Correct

Detailed Explanation

[Variation 1] Choice D is the best answer. Circumference = 2 times pi times r = 2 times pi times 4 = 8pi

Why others are wrong:

A: 10pi is incorrect because it does not satisfy the equation.

B: 4pi is incorrect because it does not satisfy the equation.

C: 16pi is incorrect because it does not satisfy the equation.