Question: Pipe A can fill a tank in 16 minutes and pipe B cam empty it in 24 minutes. If both the pipes are opened together after how many minutes should pipe B be closed, so that the tank is filled in 30 minutes?

• 1. 20
• 2. 24
• 3. 23
• 4. None of these

Question: Two pipes can fill a tank in 18 minutes and 15 minutes. An outlet pipe can empty the tank in 45 minutes. If all the pipes are opened when the tank is empty, then how many minutes will it take to fill the tank?

• 1. 12
• 2. 13
• 3. 11
• 4. 10

Question: Three pipes of same capacity can fill a tank in 8 hours. If there are only two pipes of same capacity, the tank can be filled in___________?

• 1. 17 hours
• 2. 12 hours
• 3. 16 hours
• 4. 24 hours

Question: A cistern has three pipes, A, B and C. The pipes A and B can fill it in 4 and 5 hours respectively and C can empty it in 2 hours. If the pipes are opened in order at 1, 2 and 3 A.M. When will the cistern be empty?

• 1. 3 PM
• 2. 7 PM
• 3. 4 PM
• 4. 5 PM

Question: Pipes A and B can fill a cistern in 8 and 24 minutes respectively. They are opened an alternate minutes. Find how many minutes, the cistern shall be full?

• 1. 6 min
• 2. 12 min
• 3. 19 min
• 4. 10 min

Question: A pipe can fill a cistern in 20 minutes whereas the cistern when fill can be emptied by a leak in 28 minutes. When both pipes are opened, find when the cistern will be full?

• 1. 60 min
• 2. 80 min
• 3. 70 min
• 4. 48 min

Question: A cistern which could be filled in 9 hours takes one hour more to be filled owing to a leak in its bottom. If the cistern is full in what time will the leak empty it?

• 1. 45 hrs
• 2. 60 hrs
• 3. 75 hrs
• 4. 90 hrs

Question: pipes P and Q would fill a cistern 18 and 24 minutes respectively. Both pipes being opened, find when the first pipe must be turned off so that the cistern may be just filled in 12 minutes?

• 1. after 12 mins
• 2. after 9 mins
• 3. after 8 1/2 mins
• 4. after 10 mins

Question: Two pipes function simultaneously the reservoir will be filled in 12 hours. One pipe fills reservoir 10 hours faster than the other. How many hours does the faster pipe take to fill the reservoir?

• 1. 25 hrs
• 2. 28 hrs
• 3. 20 hrs
• 4. 35 hrs

Question: Two pipes can separately fill a tank in 20 and 30 hours respectively. Both the pipes are opened to fill the tank but when the tank is full, a leak develops in the tank through which one-third of water supplied by both the pipes goes out. What is the total

• 1. 18 hrs
• 2. 16 hrs
• 3. 15 hrs
• 4. 12 hrs