We know that 1 gallon is equal to 16 cups. So 9 gallons is 144 cups. each guest eats 2.5 cups, and there are 34 guests, 2.5 times 34 = 85, the amount eaten by the guests. So to figure out whats left, subtract the eaten from the total. 144-85=59 59 is the answer. hope it helped :)
