Question

What is the area of a circle if the circumference is 30cm (express your answer in centimetres)

Answer 1

So before we can find the area, we first have to find the radius. We will do this by using the circumference formula, C = 2πr, to find the radius. Our equation will look like this: 30 = 2πr .

For this, all you need to do is divide both sides by 2π, and your answer will be 4.77 cm = r.

Now that we got the radius, we can solve for the area, which is A = πr^2.

A = π(4.77)^2

A = 22.7529π cm^2 or 71.48 cm^2