Chapter 12.10, Problem 20IP

To determine

To calculate: Lateral and surface area of the figure formed by the net.

Answer to Problem 20IP

Lateral area $=628.6Inc{h}^2$ , surface area $=942.9Inc{h}^2$

Explanation of Solution

Given information:

The given information is, a cone is formed by the given net whose base radius is 15 inches and slant height is 20 inches.

Formula used:

Lateral area $=\pi rl$ , surface area $=\pi r(r+l).$

Calculation:

  $\begin{array}{l}givenr=10inches,l=20inches.\\ \because \text{Lateral }area=\pi rl\\ =\frac{22}{7}\times 10\times 20\\ =628.6Inc{h}^2\\ surfacearea=\pi r(r+l)\\ =\frac{22}{7}\times 10\times 30\\ =942.9Inc{h}^2\end{array}$