Chapter 6, Problem 1CST

To determine

To write : the equivalent rate $\frac{15\text{ mi}}{1\text{ h}}$ .

Answer to Problem 1CST

B. $\frac{\text{1320 ft}}{1\text{ min}}$

Explanation of Solution

Given information :

Consider, the proportion

  $\frac{15\text{ mi}}{1\text{ h}}$

Calculation:

To convert from miles per hours to feet per min, divide the rate by a conversion factor. There are 60 min in one hours so, $\frac{1\text{ hours}}{60\text{ min}}=1$ and one miles = $5280$ feet therefore $15$ miles = $72900$ feet.

Therefore,

  $\begin{array}{l}\frac{15\text{ mi}}{1\text{ h}}\\ \frac{15\cdot 5280\text{ ft}}{1\cdot 60\min }\text{ = }\frac{72900\text{ ft}}{\text{60 min}}\left[\text{multiply by conversion factor}\right]\\ \frac{72900÷60\text{ ft}}{\text{60 }÷\text{60 min}}\left[\text{divide out common factor}\right]\\ \frac{1320\text{ ft}}{1\text{ min}}\end{array}$

Hence,the correct answer is B.

  $\frac{\text{1320 ft}}{1\text{ min}}$