Question

If a train maintains a constant speed of 60 miles per

hour, it can travel 4 miles per gallon of diesel fuel. If
this train begins a trip with a full 200 gallon tank of
diesel fuel, and maintains a speed of 60 miles per
hour, which of the following equations represents the
number of gallons, g, left in the tank t hours into the
trip?

Answer 1

Answer: g=200-15t

Explanation: The speed is constant at 60 mph. That means every hour, the train is going 60 miles. Since a gallon allows it to travel 4 miles, to travel 60 we need 15 gallons. And since we are going 60 miles every hour, we are using 15 gallons an hour. So we start with 200 gallons, and every hour, t, we use 15 gallons to get gallons (g)=200-15t