I'm assuming that you want to find the unit rate of both scenarios.
I'm going to assume that you meant 112 miles in 8 hours.
Divide to find the unit rate: 112 / 8 = 14 miles per hour.
150 miles in 6 gallons
Divide to find the unit rate: 150 / 6 = 25 miles per gallon.
Best of Luck!