Question

Circle O has a circumference of 36 pi cm. What is the length of the radius, r?

Answer 1

The circumference of a circle is C = 2πr
Given C = 36π, we can solve for the radius r:
r = C/2π = 36π/2π = 36/2 = 18 cm (ANSWER)

Answer 2

The radius of the circle is 18 cm.

Explanation:

The circumference of circle O is 36π cm.

The formula for circumference of circle is

`C=2\pi r`

Where, r is the radius of the circle.

Put C=36π, to find the radius of the circle.

`36\pi=2\pi r`

Divide both sides by 2π.

`(36\pi)/(2\pi)=r`

`18=r`

Therefore the radius of the circle is 18 cm.