Quiz Discussion

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]

  hours

• 3]

  7 hours

• 4]

  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]

  

• 2]

  

• 3]

  

• 4]

  

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

A water tank is two-fifth full.Pipe A can fill a tank in 10 minutes and pipe B can empty it in 6 minutes.If both the pipes are open,how long will it take to empty or fill the tank completely?

• 1]

  6 min to empty

• 2]

  6 min to fill

• 3]

  9 min to empty

• 4]

  9 min to fill

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

Having the same capacity 9 taps fill up a water tank in 20 minutes. How many taps of the same capacity are required to fill up the same water tank in 15 minutes ?

• 1] 10 taps
• 2] 12 taps
• 3] 15 taps
• 4] 18 taps

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

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 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

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