Quiz Discussion

A cistern has two taps which fill it in 12 minutes and 15 minutes respectively. There is also a waste pipe in the cistern. When all the pipes are opened, the empty cistern is full in 20 minutes. How long will the waste pipe take to empty the full cistern?

• 1]

  12 min

• 2]

  10 min

• 3]

  8 min

• 4]

  16 min

Two pipes A and B together can fill a cistern in 4 hours. Had they been opened separately, then B would have taken 6 hours more than A to fill the cistern. How much time will be taken by A to fill the cistern separately?

• 1] 1 hour
• 2] 2 hours
• 3] 6 hours
• 4] 8 hours

A pipe can fill a tank in 3 hours. There are two outlet pipes from the tank which can empty it in 7 and 10 hours respectively. If all the three pipes are opened simultaneously, then the tank will be filled in -

• 1] 8 hours
• 2] 9 hours
• 3] 10 hours
• 4] 11 hours

A pipe can fill a tank in x hours and another pipe can empty it in y (y > x) hours. If both pipes are open, in how many hours will the tank is filled?

• 1]

  (x - y) hours

• 2]

  (y - x) hours

• 3]

  hours

• 4]

  hours

Pipe A can fill the tank in 8 hours and pipe B can fill it in 12 hours. If pipe A is opened at 7:00 AM and pipe B is opened at 9:00 AM, then at what time will the tank be full ?

• 1] 12:00 PM
• 2] 12:30 PM
• 3] 11:48 PM
• 4] 12:36 PM

An outlet pipe can empty a cistern in 3 hours. In what time will empty 2/3 of the cistern?

• 1] 3 hours
• 2] 5 hours
• 3] 2 hours
• 4] 4 hours

A large tanker can be filled by two pipes A and B in 60 minutes and 40 minutes respectively. How many minutes will it take to fill the tanker from empty state if B is used for half the time and A and B fill it together for the other half?

• 1] 15 minutes
• 2] 20 minutes
• 3] 27.5 minutes
• 4] 30 minutes

Pipe A can fill a tank in 4 hours and pipe B can fill it 6 hours. If they are opened on alternate hours and if pipe A is opened first then in how many hours, the tank shall be full ?

• 1]

  hours

• 2]

  hours

• 3]

  hours

• 4]

  hours

Two pipes A and B can fill a tank with water in 30 minutes and 45 minutes respectively. The third pipe C can empty the tank in 36 minutes. First A and B are opened. After 12 minutes C is opened. Total time ( in minutes ) in which the tank will be filled up is -

• 1] 12 minutes
• 2] 24 minutes
• 3] 30 minutes
• 4] 36 minutes

An electric pump can fill a tank in 3 hours. Because of a leak in the tank, it  took 321​ hours to fill the tank. The leak can drain all the water off the tank in

• 1]

  12 hours

• 2]

  10 1/2 hours

• 3]

  6 1/2 hours

• 4]

  21 hours