He needs to triple his recipe by 3, so 12 x 3. So you get 36. The question was how many quarts does he need. So 36 divided by 2 is 18. So 18 quarts is needed!
Part B: We need to find out how many gallons he needs, we already know that he has 18 quart. There are 4 quarts in a gallon. So 18 divided by 4 is 4 1/2.
