Pipes and Cistern Questions

• Pipe K fills a tank in 30 minutes. Pipe L can fill the same tank 5 times as fast as pipe K. If both the pipes were kept open when the tank is empty, how much time will it take for the tank to overflow ?
• A Tank is normally filled in 9 hours but takes four hours longer to fill because of a leak in its bottom. If the tank is full, the leak will empty it in ?
• A water tank has holes. The 1st hole alone empties the tank in 9 min and 2nd hole alone empties the tank in 6 min. If water leaks out at a constant rate, how many min does it take if both the holes together empty the tank?
• Two pipes A and B can fill a tank in 15 min and 20 min respectively. Both the pipes are opened together but after 4 min, pipe A is turned off. What is the total time required to fill the tank ?
• Two pipes A and B can separately fill a cistern in 60 min and 75 min respectively. There is a third pipe in the bottom of the cistern to empty it. If all the three pipes are simultaneously opened, then the cistern is full in 50 min. In how much time, the third pipe alone can empty the cistern ?
• In what time would a cistern be filled by three pipes which diameters are 2 cm, 3 cm and 4 cm running together, when the largest alone can fill it is 58 minutes? The amount of water flowing in each pipe is proportional to the square of its diameter.
• One pipe can fill a tank three times as fast as another pipe. If together the two pipes can fill tank in 36 min, then the slower pipe alone will be able to fill the tank in ?
• 3 pipes when opened for 3 hours can fill 3 buckets. How many buckets can 2 pipes open for 2 hours approximately fill?
• A water tank is filled in 5 hours by three pipes X, Y and Z the pipe Z is thrice as fast as Y and Y is twice as fast as X. How much time will pipe X alone take to fill the water tank?
• A tank is filled in eight hours by three pipes K, L and M. Pipe K is twice as fast as pipe L, and L is twice as fast as M. How much time will pipe L alone take to fill the tank ?
• Three pipe P, Q and R can fill a tank in 12 minutes, 18 minutesand 24 minutes respectively. The pipe R is closed 12 minutesbefore the tank is filled. In what time the tank is full?
• Pipes A and B can fill a cistern in 15 hours together. But ifthese pipes operate separately A takes 40 hours less than Bto fill the tank. In how many hours the pipe A will fill thecistern working alone?
• 18 buckets of water fill a tank when the capacity of each bucket is 8 litres. How many buckets will be needed to fill the same tank, if the capacity of the bucket is 12 litres?
• A water tank is 2/5 th full. Inlet A can fill the tank in 12 minutes while an outlet pipe B can empty it in 6minutes. If both the pipes are open, how long will it take to empty or fill the tank completely?
• A cistern has one inlet, L and one inlet, M. L takes 5 hours to fill the empty tank, when M is not open and M takes 8 hours to empty the full tank, if the tank is two fifth full, how much time will it take to fill the tank completely when both L and M are opened simultaneously? (in hours)
• An electric pump can fill a tank in 2 hours. Because of a leak in the tank, it was taking 21⁄2 hours to fill the tank. The leak can drain all the water off the tank in how many hours?
• Two pipes, when working one at a time, can fill a cistern in 3 hhrs and 4 hrs, resp while a third pipe can drain the cistern empty in 8 hrs. All the three pipes were opened together when the cistern was 1/12 full. How long did it take for the cistern to be completely full?
• A swimming pool is filled in 10 hours by three tankers A, B and C. The tanker C is twice as fast as B and B is twice as fast as A. How much time will tanker A alone take to fill the swimming pool?
• Two taps X and Y can fill a tank in 15 hours and 20 hours respectively. If the two taps are opened at 2 p.m., then at what time (in p.m.) should the tap X be closed to completely fill the tank at exactly 2 a.m.?