Chapter 12, Problem 4PT

To determine

To calculate : The lateral area and surface area.

Answer to Problem 4PT

The lateral area $L=52.7i{n}^2$ and the surface area. $S=65i{n}^2$

Explanation of Solution

Given information : The circular Piller is $2.8$ inches wide and $6$ inches tall.

Formula used : The lateral area of the cylinder is $L=2\pi rh$ and the surface area will be $S=2\pi r^2+2\pi rh$ . Where $r$ is the radius and $h$ is the height of the cylinder.

Calculation : Calculate the radius.

The radius is half of the circular base.

  $r=\frac{2.8}{2}=1.4$ inches

Now, find the lateral area.

  $L=2\pi rh$

  $\begin{array}{l}L=2\pi \times 1.4\times 6\\ L=52.7i{n}^2\end{array}$

And the surface area would be

  $\begin{array}{l}S=2\pi r^2+2\pi rh\\ S=(2\pi \times {1.4}^2)+(2\pi \times 1.4\times 6)\\ S=12.3+52.7\\ S=65i{n}^2\end{array}$