Solve the Problem $40 \mathrm{mph}$ And the Other Travels At $52 \mathrm{mph}$

Multiple Choice

Solve the problem.
-Two cars leave town at the same time going in the same direction. One travels at $40 \mathrm{mph}$ and the other travels at $52 \mathrm{mph}$ . In how many hours will they be $48 \mathrm{mi}$ apart?

A) $1 \mathrm{hr}$
B) $40 \mathrm{hr}$
C) $4 \mathrm{hr}$
D) $12 \mathrm{hr}$