7

Set 5: Circles (Beginner)

Explanation

Answer: B

PROBLEM

Intriguingly, a circle has radius 7. What is its circumference? (Express answer as a number times pi)

A circle has radius 7. What is its circumference? (Express answer as a number times pi)

A.

49pi

B.

14pi

✓ Correct
C.

16pi

D.

7pi

Detailed Explanation

[Variation 2] Choice B is the best answer. Circumference = 2 times pi times r = 2 times pi times 7 = 14pi

Why others are wrong:
A: 49pi is incorrect because it does not satisfy the equation.
C: 16pi is incorrect because it does not satisfy the equation.
D: 7pi is incorrect because it does not satisfy the equation.