How many gallons of water to fill a 16inches wide by 12 inches deep by 48 inches long?

1 gallon of water = 231 cubic inches. To find the capacity (volume): L x W x D. 16 x 12 x 48 = 9216 cubic inches. Divide by 231 to find how many gallons of water. 9216 ÷ 231 = 39.896103 gallons.