Chapter 11.4, Problem 21PPS

(a)

To determine

To find: The area of the paper that is needed to make one envelope.

Answer to Problem 21PPS

The area of the paper is $60.95{\text{in}}^2$ .

Explanation of Solution

Given:

The given diagram is shown in Figure 1

  

Figure 1

Calculation:

Consider the width of the paper is calculated as,

  $\begin{array}{c}w=5.5+\frac{1}{8}+\frac{1}{8}\\ =5.75\text{in}\end{array}$

Then, the length of the paper is calculated as,

  $\begin{array}{c}l=4+4+2\frac{2}{3}\\ =10\frac{2}{3}\\ =10.6\end{array}$

Then, the area of the paper is,

  $\begin{array}{c}A=10.6\left(5.75\right)\\ =60.95{\text{in}}^2\end{array}$

(b)

To determine

To find: The number of envelop that can be made.

Answer to Problem 21PPS

The number of envelope that is can be made is $14$ .

Explanation of Solution

Given:

The dimension of the paper is 2 feet by 4 feet.

Calculation:

Consider the area of the paper is,

  $\begin{array}{c}A=2\text{ft}\times 3\text{ft}\\ =\text{6}{\text{ft}}^2\end{array}$

The area of the paper in square inch is,

  $\begin{array}{c}6{\text{ft}}^2=6\text{ft}\times \frac{144\text{sq}\text{in}}{1{\text{ft}}^2}\\ =864{\text{in}}^{\text{2}}\end{array}$

Thus, the number of envelope that can be made is,

  $\begin{array}{c}\frac{864{\text{in}}^{\text{2}}}{61}=14.2\\ \approx 14\end{array}$