PLSSS HELP FOR BRAINLIEST

Answer:
the answer is 12 gallons
Step-by-step explanation:
make fractions improper:
9/8 and 25/2
make them have a common denominator:
9/8 and 100/8
to make a whole gallon but what you do to one side you do to the other:
9/8-1/8=8/8
100/8-1/8=99/8
divide 99/8:
12.375
round down:
12