There are a couple of steps to solve this problem:
Find the total number of cups of water in a case of water.
Convert the total number of cups to gallons.
To find the total number of cups of water in a case of water, we can multiply the number of bottles in a case (64) by the number of cups in each bottle (3 1/2):
64 x 3 1/2 = 224 cups
To convert cups to gallons, we can divide the number of cups by the number of cups in a gallon. There are 16 cups in a gallon, so we can divide 224 by 16:
224 cups / 16 cups/gallon = 14 gallons
Therefore, there are 14 gallons of water in a case of water.