Quiz Discussion

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

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 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

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

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 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

One pipe can fill a tank three times as fast as another pipe. If together the two pipes can fill the tank in 36 minutes, then the slower pipe alone will be able to fill the tank in:

• 1] 81 minutes
• 2] 108 minutes
• 3] 144 minutes
• 4] 192 minutes

Three taps A, B, C can fill an overhead tank in 4, 6 and 12 hours respectively. How long would the three taps take to fill the tank if all of them are opened together ?

• 1] 2 hours
• 2] 4 hours
• 3] 3 hours
• 4] 5 hours

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

Pipe A can fill the tank in 8 hours and pipe B can fill it in 12 hours. If pipe A is opened at 7:00 AM and pipe B is opened at 9:00 AM, then at what time will the tank be full ?

• 1] 12:00 PM
• 2] 12:30 PM
• 3] 11:48 PM
• 4] 12:36 PM