Answer: 24 cakes
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Work Shown:
1 gallon = 16 cups
3 gallons = 48 cups ... multiply both sides by 3
(2 cups of milk)/(1 cake) = (48 cups of milk)/(x cakes)
2/1 = 48/x
2x = 1*48
2x = 48
x = 48/2
x = 24
He can make 24 cakes.