Quiz Discussion

Three pipes P, Q and R can separately fill a cistern in 4, 8 and 12 hours respectively. Another pipe S can empty the completely filled cistern in 10 hours. Which of the following arrangements will fill the empty cistern in less time than others?

• 1] Q alone is open
• 2] P, R and S are open
• 3] P and S are open
• 4] P, Q and S are open

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

A tank has a leak which would empty the completely filled tank in 10 hours. If the tank is full of water and a tap is opened which admits 4 litres of water per minute in the tank , the leak takes 15 hours to empty the tank. How many litres of water does the tank hold?

• 1] 2400 litters
• 2] 4500 litters
• 3] 1200 litters
• 4] 7200 litters

Two pipes A and B can fill a cistern in 37.5 minutes and 45 minutes respectively. Both pipes are opened. The cistern will be filled in just half an hour, if the B is turned off after:

• 1] 5 min.
• 2] 9 min.
• 3] 10 min.
• 4] 15 min.

Pipes A and B can fill a tank in 5 and 6 hours respectively. Pipe C can empty it in 12 hours. If all the three pipes are opened together, then the tank will be filled in:

• 1]

  1 13/17 hours

• 2]

  2 8/11 hours

• 3]

  3 9/17 hours

• 4]

  4 1/2 hours

A tank with capacity T liters is empty. If water flows into the tank from pipe X at the rate of x liters per minute and water is pumped out by Y at the rate of y liters per minute and x > y, then how many minutes will the tank be filled?

• 1]

  (x - y) 60 T minutes

• 2]

  (T - x) minutes

• 3]

    minutes

• 4]

   minutes

A vessel has three pipes connected to it , two to supply liquid and one to draw liquid. The first alone can fill the vessel in hours, the second in 3 hours and the third can empty it in hours. If all the pipes are opened simultaneously when the vessel is half full, how soon will it be emptied?

• 1]

  hours

• 2]

   hours

• 3]

  hours

• 4]

  None of these

Two pipes can fill a tank in 12 hours and 16 hours respectively. A third pipe can empty the tank in 30 hours. If all three pipes are opened and functions simultaneously, how much time will the tank take to be full?( in hours )

• 1]

  

• 2]

  

• 3]

  

• 4]

  

A tap can fill a tank in 6 hours. After half the tank is filled, three more similar taps are opened. What is the total time taken to fill the tank completely?

• 1] 3 hrs 15 min
• 2] 3 hrs 45 min
• 3] 4 hrs
• 4] 4 hrs 15 min

A swimming pool is filled by three pipes with uniform flow. The first two pipes operating simultaneously fill the pool in the same time during which the pool is filled by the third pipe alone. The second pipe fills the pool 5 hours faster than the first pipe and 4 hours slower than the third pipe. The time required by the first pipe is?

• 1] 6 hours
• 2] 10 hours
• 3] 15 hours
• 4] 30 hours