Chapter 6.1, Problem 30E

To determine

To calculate: The equivalent rate.

Answer to Problem 30E

The equivalent rate is $79200$ feet per hour.

Explanation of Solution

Given information:

The following equivalent fractions:

  $\frac{15\text{ mi}}{1\text{ h}}=\frac{?\text{ ft}}{1\text{ h}}$

Calculation:

To find an equivalent rate, convert from miles per hour to feet per hour. To do so, multiply the rate by a conversion factor. There are $5280$ feet in $1$ mile, so $\frac{5280\text{ ft}}{1\text{ mi}}=1$ .

  $\begin{array}{l}\frac{15\text{ mi}}{1\text{ hr}}\\ \Rightarrow \frac{15\text{ mi}}{1\text{ hr}}\times \frac{5280\text{ ft}}{1\text{ mi}}\left[\text{Multiply rate by common conversion factor}\right]\\ \Rightarrow \frac{15\cancel{\text{mi}}}{1\text{ hr}}\times \frac{5280\text{ ft}}{1\cancel{\text{mi}}}\left[\text{Divide out common factor and unit}\right]\\ \Rightarrow \frac{79200\text{ ft}}{1\text{ hr}}\left[\text{Simplify}\right]\end{array}$

Therefore, The equivalent rate is $79200$ feet per hour.