Chapter 8.5, Problem 53STP

To determine

To calculate the time Rafael drive before he caught up with Monica

Answer to Problem 53STP

Rafael drive for 6 hours before he caught up with Monica. The correct answer is option C.

Explanation of Solution

Given information:

Rafael drove toward the cabin at an average speed of 40 km per hour

Monica drove in same direction at an average speed of 48 km per hour

Monica drive for 5 hours then she caught up with Rafael

For Rafael, $d=40t_R$ [here $d$ is direction and $t$ is the time]

For Monica, $d=48t_M$ [here $d$ is direction and $t$ is the time]

As $d$ is equal for both equation so set them equal to each other

  $48t_M=40t_R$

Now, put 5 in Monica’s time as she drive for 5 hours,

  $\begin{array}{l}48t_M=40t_R\\ 48\left(5\right)=40t_R\\ 240=40t_R\\ \frac{240}{40}=t_R\\ t_R=6\end{array}$

Therefore, it is obtained that Rafael drive for 6 hours.

Rafael drive for 6 hours before he caught up with Monica. The correct answer is option C.