A. 81 min.
B. 108 min.
C. 144 min.
D. 192 min.
Pipes and Cisterns
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?
A. 20
B. 24
C. 23
D. None of these
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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 solution R in the liquid in the tank after 3 minutes?
A. 5/11
B. 6/11
C. 7/11
D. 8/11
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Two pipes A and B can fill a cistern in 12 and 15 minutes respectively. Both are opened together but after 3 minutes A is turned off. After how much more time will the cistern be filled?
A. 3 1/4 min
B. 5 1/4 min
C. 8 1/4 min
D. 9 1/4 min
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Two taps can separately fill a cistern 10 minutes and 15 minutes respectively and when the waste pipe is open, they can together fill it in 18 minutes. The waste pipe can empty the full cistern in?
A. 7 min
B. 13 min
C. 23 min
D. 9 min
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Two pipes A and B can fill a cistern in 37 1/2 minutes and 45 minutes respectively. Both pipes are opened. The cistern will be filled in just half an hour, if the pipe B is turned off after?
A. 5 min
B. 9 min
C. 10 min
D. 15 min
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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?
A. 6 min
B. 12 min
C. 19 min
D. 10 min
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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?
A. 3 PM
B. 7 PM
C. 4 PM
D. 5 PM
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Two pipes A and B together can fill a cistern in 4 hours. Had they been opened separately, then B would have taken 6 hours more than A to fill cistern. How much time will be taken by A to fill the cistern separately?
A. 1 hr
B. 2 hrs
C. 6 hrs
D. 8 hrs
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Two pipes A and B can fill a tank in 15 min and 20 min respectively. Both the pipes are opened together but after 4 min, pipe A is turned off. What is the total time required to fill the tank?
A. 10 min 20 sec
B. 11 min 45 sec
C. 12 min 30 sec
D. 14 min 40 sec
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