Answer:
23.5 gallons
Explanation:
The gas tank in Daniel's car has a capacity of 19.1 gallons.
On a trip to see his best friend Daniel begins with 12.8 gallons of gas in the tank.
He stops after driving for 2 hours and fills the tank to capacity with 14.4 gallons.
When Daniel arrives at his friend's house, he has 3.7 gallons of gas left.
Total amount of gas filled was (12.8 + 14.4) = 27.2 gallons.
The amount of gas remaining after the trip was 3.7 gallons
The amount of gas, in gallons, used by Daniel on his trip was 27.2 - 3.7 = 23.5 gallons