Question

To the nearest tenth of a centimeter, what is the circumference of a circle with a radius of 2.5 cm? (Use 3.14 for π.)

Answer 1

To find a circumference of a circle you have to use this expression: C = dπ. d stands for the diameter, so let's find that first.

To find the diameter multiply the radius by 2.
2.5 x 2 = 5

Let's rewrite our equation now. C = 5 · π
15.71 = 5 · π

The answer is 15.71