Royston's car had 15 1/5 gallons of gas at the start of the trip. During the trip, he stopped at a gas station and he refueled the car with 5 3/5 gallons. If the car consumed 17 4/5 gallons of gas during the trip, there are still ____________ gallons of gas remaining in the tank?
15 1/5 + 5 3/5 = 20 4/5
that is the total gallons of gas avalible
but they only used 17 4/5, so
20 4/5 - 17 4/5 = 3
so he only had 3 galons left after the trip