Question

Jayden is driving on a long road trip. He currently has 11 gallons of gas in his car. Each hour that he drives, his car uses up 0.75 gallons of gas. How much gas would be in the tank after driving for 4 hours? How much gas would be left after t hours?

Answer 1

a. 8 gallons

b. (11-0.75t) gallons

Explanation:

a. Here in this question, we are told that the total amount of fuel in the fuel tank is 11 gallons and the car consumes 0.75 gallon per hour. We are interested in knowing the amount of fuel left in the tank after driving for four hours.

We proceed as follows;

Since 0.75 gallon is consumed in an hour, the amount of fuel consumed in 4 hours would be the amount consumed in an hour * 4 hours

Mathematically, that would be 0.75 * 4 = 3 gallon

Now, the amount of fuel left is simply the difference between the initial amount of fuel in the tank minus the amount of fuel present after 4 hours.

That would be; 11 - 3 = 8 gallons

b. Like above, we want to know the amount of fuel left after t hours.

Since 0.75 is used up per hour, the amount used up in t hours would be 0.75 * t = 0.75t

Now, the amount of fuel that would be left in the tank would be the difference between what we had initially and what was used up.

Mathematically, that would be 11- 0.75t