The local zoo had two water tanks that are leaking. One tank contains 12 gallons of water and is leaking at a constant rate of 3 gallons per hour. The second tank contains 8 gallons of water and is leaking at a constant rate of 5 gallons per hour. When will the two tanks have the same amount of water.

Answer :

Once they're empty, I guess.
Did you put it the wrong way around?
Because it would be after four hours in this case.