Chapter 11.1, Problem 61S

To determine

To find: The average rate in miles per hour for the entire trip.

Answer to Problem 61S

The average rate in miles per hour for the entire trip is $63\text{miles per hour}$ .

Explanation of Solution

Given Information:

Total time taken in the entire trip is $10\text{h}$ , the rate of the trip for the first four is $60\text{miles}\text{per hour}$ , and the rate of the remaining trip is $65\text{miles}\text{per hour}$ .

The average rate in miles per hour for the entire trip is calculated as,

  $\begin{array}{c}V=\frac{4\times 60+6\times 65}{10}\\ =\frac{240+390}{10}\\ =63\text{miles per hour}\end{array}$

Thus, the average rate in miles per hour for the entire trip is $63\text{miles per hour}$ .