let's firstly convert the mixed fractions to improper fractions and then to do away with the denominators, let's multiply both sides by the LCD of all denominators.
He made 3.75 gallons. There was 1/10 remaining, meaning each tenth was 6 cups. The entire thing is 10 tenths so you do 6(10) to get 60 cups. After converting to gallons by doing 60÷26, you get 3.75.
