Quiz Discussion

A pipe can fill a tank in x hours and another can empty it in y hours. In how many hours they together fill it in ( y > x) ?

• 1]

  (x - y) hours

• 2]

  (y - x) hours

• 3]

   hours

• 4]

  hours

Two pipes A and B can fill a tank in 20 and 30 minutes respectively. If both the pipes are used together, then how long it will take to fill the tank ?

• 1]

  10 mins

• 2]

  12 mins

• 3]

  15 mins

• 4]

  20 mins

Two pipes A and B can fill a tank in 15 minutes and 20 minutes respectively. Both the pipes are opened together but after 4 minutes, pipe A is turned off. What is the total time required to fill the tank?

• 1] 10 min. 20 sec.
• 2] 11 min. 45 sec.
• 3] 12 min. 30 sec.
• 4] 14 min. 40 sec.

A tap can completely fill a water tank in 8 hours. The water tank has a hole in it through which the water leaks out. The leakage will cause the full water tank to get empty in 12 hours. How much time will it take for the tap the the tank completely with the hole?

• 1] 16 hours
• 2] 18 hours
• 3] 24 hours
• 4] None of these

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

A tank is 7 metre long and 4 meter wide wide. At what speed should water run through a pipe 5 cm broad and 4 cm deep so that in 6 hours and 18 minutes water level in the tank rises by 4.5 meter?

• 1] 10 km/hours
• 2] 12 km/hours
• 3] 8 km/hours
• 4] None of these

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 A and B can fill a tank in 20 and 30 hours respectively. Both the pipes are opened to fill the tank but when the tank is one - third full, a leak develops in the tank through which one - third water supplied by both the pipes gose out. The total time taken to fill the tank is?

• 1] 12 hours
• 2] 14 hours
• 3] 16 hours
• 4] 18 hours

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]

  5/11

• 2]

  6/11

• 3]

  7/11

• 4]

  8/11

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