The fuel capacity of a popular hybrid car is 11.9 gallons. The function for this situation is f(x) = -0.02x + 11.9, where x represents miles and f(x) represents the amount of fuel remaining. What is the rate of change for this scenario?
You're in luck. The fuel consumption of the car is linear, and the slope - ie, the coefficent of the x term gives you the rate of change. In this case, it's -0.02 gallons per mile.