# Two pipes X and Y can separately fill a tank in 12 and 15 minutes respectively. A third pipe Z can drain off 45 liters of water per minute. If all the pipes are opened, the tank can be filled in 15 minutes.Â What is the capacity of the tank?

**Two pipes X and Y can separately fill a tank in 12 and 15 minutes respectively. A third pipe Z can drain off 45 liters of water per minute. If all the pipes are opened, the tank can be filled in 15 minutes.Â What is the capacity of the tank?**