Question

A ring-shaped region is shown below. Its inner radius is 15 in. The width of the ring is 4 in. Find the area of the shaded region. Use 3.14 for π. Do not round your answer.

Answer 1

The Solution:

Given:

Required:

To find the area of the shaded region.

The area of the shaded region is:

$Area=\pi R^2-\pi r^2=\pi(R^2-r^2)$

In this case,

$\begin{gathered} R=15+4=19\text{ inches} \\ \\ r=15\text{ inches} \end{gathered}$

Substitute:

$undefined$