Question

A circle with radius of 2cm sits inside a circle with radius of 4cm What is the area of the shaded region

Answer 1

ANSWER

$12\pi \: {cm}^{2}$

EXPLANATION

We want to find the area of the shaded region.

We find the area of the smaller circle and subtract from the area of the larger circle.

Area of smaller circle is

$a = \pi \: \times 2^{2} = 4\pi$

Area of larger circle is

$A = \pi \: \times {4}^{2} = 16\pi$

The area of the shaded region is:

$16\pi - 4\pi = 12\pi$