Quiz Discussion

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

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 pipe A and B can fill a water tank in 20 and 24 minutes respectively and a third pipe C can empty at the rate of 3 gallons per minute. If A, B and C are open together to fill the tank in 15 minutes, find the capacity of tank?

• 1] 180 gallons
• 2] 150 gallons
• 3] 120 gallons
• 4] 60 gallons

Three pipes A, B and C can fill a tank from empty to full in 30 minutes, 20 minutes, and 10 minutes respectively. When the tank is empty, all the three pipes are opened. A, B and C discharge chemical solutions P, Q and R respectively. What is the proportion of the solution R in the liquid in the tank after 3 minutes?

• 1]

  

• 2]

  

• 3]

  

• 4]

  

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.

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

Two pipes can fill a tank in 20 and 24 minutes respectively and a waste pipe can empty 3 gallons per minute. All the three pipes working together can fill the tank in 15 minutes. The capacity of the tank is:

• 1] 60 gallons
• 2] 100 gallons
• 3] 120 gallons
• 4] 180 gallons
• 5] None of these

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

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

Three taps A, B and C can fill a tank in 12,15 and 20 hours respectively. If A is open all the time and B and C are open for one hour each alternately, the tank will be full in.

• 1]

  6 hours

• 2]

  6 2/3 hours

• 3]

  7 hours

• 4]

  7 1/2 hours