Answer: 1 3/4 gallons
Step-by-step explanation: In order to determine the total number of gallons in the recipe you need to convert 8 cups to gallons. There are 16 cups in 1 gallon. In order to determine how many gallons 8 cups is you need to divide 8/16 = 1/2 gallon.
The total number of gallons is 1 1/4 + 1/2.
1 1/4 + 1/2 = 1 3/4 gallons.