Final answer:
The truck used approximately 25 gallons of fuel for the 5-hour trip.
Step-by-step explanation:
To determine the total gallons of fuel used by the truck for the 5-hour trip, we need to multiply the average speed (60 miles per hour) by the duration of the trip (5 hours) to find the total distance traveled. So, 60 miles per hour x 5 hours = 300 miles. Next, we divide the total distance traveled by the fuel consumption rate (12 miles per gallon) to find the number of gallons of fuel used. Therefore, 300 miles / 12 miles per gallon = 25 gallons of fuel used for the 5-hour trip.