Chapter 6.8, Problem 18PPS

To determine

To Find: The distance she should place the projector.

Answer to Problem 18PPS

  $32yards$

Explanation of Solution

Given:Felicia wants to project a $2$ inch slide on the wall to create an image $128$ inches by $128$ inches. If the slide projector makes the dimensions of the image twice as large for each yard that is moved away from the wall, how far away should Felicia place the projector?

Let number of yards required to make an image $128$ inches by $128$ inches = $x$

Since each yard doubles the dimensions

Thus

Multiply it by $2$ from the original of two.

i.e.

  $2(2x)=128$

Solve for $x$

We get

  $\begin{array}{l}2(2x)=128\\ 4x=128\\ x=\frac{128}{4}\\ x=32yards\end{array}$

Hence, she should place the projector $32yards$ far away.