The answer would be 9 gallon because you would multiply 48 and 3 the divide the answer (144) by 16 (how many cups in one gallon and get you answer, 9. hope this helps :)
I would say 9. I may have calculated this wrong but she expects each guest to drink 3 cups so 48x3= 144 cups. There are 16 cups to a gallon. 144cups/ 16cups= 9 gallons
