Question

How do you do this??

Answer 1

131.964 cm

Explanation:

`C = 2 \pi r = 2 * 3.142 * 21 = 3.142 * 42 = 131.964 \ cm`

Answer 2

The formula for the circumference of a circle = 2 x radius x pi

The radius is given as 21 cm and pi = 3.142

Circumference = 2 x 21 x 3.142 = 131.964 cm