Answer: 9 gallons, 15 cups
Explanation:
Note that 1 gallon = 16 cups
Since at the beginning of the auction, the tank had 10 gallons of water in it, and thirty minutes later, 1 cup of water had leaked out .
The amount of water that was left in the tank will be:
= 10 gallons - 1 cup
= 9 gallons, 15 cups