If I drive my car 54 miles per hour on a full tank of gas, it will run for 8 hours. For every mile per hour I speed up, the car will run 10 minutes less. For every mile I slow down, the car will run 10 minutes more.

A. Suppose I speed up by x miles per hour where x is negative if I slow down. In terms of x, what is my speed?

B. In terms of x, for how many hours will my car run?

C. What is the longest distance I can go on one tank of gas?

D. What speed would I need to go in order to go this distance?

Guest Oct 15, 2021