Question

4. A circle has a radius of 4 inches. What is the circumference of the circle?

A.4 π inches
B.8 π inches
C.12π inches
D.16π inches

Answer 1

Circumference formula:

C=πd

Input the diameter. The diameter is the distance across the circle, so it is the radius doubled or 2r. We are given a radius of 4in., so the diameter is 2•4, which is 8in.

C=π(2•4)

C=π(8)

So, the answer is option B.