Answer:
The speed of the slower car is: 51 miles/hour and the speed of the faster car is 54 miles/hour.
Explanation:
First, we can easily find the speed of the slower car, since we know that the speed is given by the formula v=d/t, where d stands for the traveled distance and t for the elapsed time.

Next, for the faster car, we know that the distance traveled is 153+9 miles in the same time, therefore, its speed is given by:
