Chapter 12.5, Problem 12PPS

To determine

The number of additional gallons is to be calculated.

Answer to Problem 12PPS

The additional gallon of $0.4gallon$ paint needed by Hinto to cover the rectangualr bedroom wall.

Explanation of Solution

Given:

  $\begin{array}{l}l=20ft\\ w=15ft\\ h=8ft\end{array}$

Paint of $1gallon$ needed for painting the $400f{t}^2$

Concept Used:

The lateral area of the rectangualr bedroom wall is given by the following expression:

  $\begin{array}{l}A=PH\\ A=2\left(w+l\right)h\end{array}$

Where,

Length of rectangualr bedroom wall: $l$

Width of rectangualr bedroom wall: $b$

Height of rectangualr bedroom wall: $h$

Perimeter of rectangualr bedroom wall: $P$

Calculation:

The lateral area of the rectangualr bedroom wall is given by the following expression:

  $A=2\left(w+l\right)h$

Put the given data:

  $\begin{array}{l}A=2\left(w+l\right)h\\ A=2\left(15+20\right)8\\ A=560f{t}^2\end{array}$

Now, if hinto required the paint of $1gallon$ needed for painting the $400f{t}^2$ , the need to calculate the additional gallon paint to cover the $560f{t}^2$ of the rectangualr bedroom wall:

  $\begin{array}{l}{A}_g=\frac{1}{400}\times 560\\ A_g=1.4gallon\end{array}$

So, the additional gallon is: $1.4gallon-1.4gallon=0.4gallon$

Conclusion:

Hence, additional gallon is $0.4gallon$