Quiz Discussion

Three pipes A, B and C can fill a tank in 6 hours. After working at it together for 2 hours, C is closed and A and B can fill the remaining part in 7 hours. The number of hours taken by C alone to fill the tank is:

• 1] 10
• 2] 12
• 3] 14
• 4] 16

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 tank can be filled by pipe A in 2 hours and pipe B in 6 hours. At 10 A.M. pipe A was opened. At what time will the tank be filled if pipe B is opened at 11 A.M. ?

• 1] 12.45 A.M.
• 2] 5 P.M.
• 3] 11.45 A.M.
• 4] 12 P.M.

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 water tap fills a tub in 'p' hours and a sink at the bottom empties it in 'q' hours. If p < q and both tap and sink are opened the tank is filled in 'r' hours, then the relation between p, q, r :

• 1]

  1/r = 1/p +1/q

• 2]

  1/r = 1/p -1/q

• 3]

  r = p + q

• 4]

  r = p - q

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 tank is filled in 5 hours by three pipes A, B and C. The pipe C is twice as fast as B and B is twice as fast as A. How much time will pipe A alone take to fill the tank?

• 1] 20 hours
• 2] 25 hours
• 3] 35 hours
• 4] Cannot be determined
• 5] None of these

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 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

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