A cistern can be filled by two pipes filling separately in 12 and 16 min respectively. Both pipes are opened together for a certain time but being obstructions, only 7/8 of full quantity water flows through the former and only 5/6 through the latter pipe. The obstructions, however, being suddenly removed, the cistern is filled in 3 minutes from that moment. How long was it obstructions before the full flow began?

A cistern can be filled by two pipes filling separately in 12 and 16 m

1.	A cistern can be filled by two pipes filling separately in 12 and 16 min respectively. Both pipes are opened together for a certain time but being obstructions, only 7/8 of full quantity water flows through the former and only 5/6 through the latter pipe. The obstructions, however, being suddenly removed, the cistern is filled in 3 minutes from that moment. How long was it obstructions before the full flow began?
A.	4.5 min
B.	2.5 min
C.	3.5 min
D.	5.5 min
Answer» B. 2.5 min

Discussion

No Comment Found

Related MCQs

A pump can fill a cistern in 40 minutes and another pump can empty the filled up cistern in 1 hour. By mistake, without closing the second pump, the first pump is opened. The time in which the empty cistern will be filled up is
Pipes A and B are emptying pipes and can empty a tank in 6 hours and 16 hours, respectively. C is a filling a pipe. All the three pipes were opened together. They took 80 minutes to empty $$ {5 over 8}th$$ of the tank. Pipe C alone can fill the tank in:
Two pipes A and B can fill a cistern in 24 minutes and 30 minutes respectively. Both are opened together, but at the end of 6 minutes the first is turned off. How much longer pipe B will take to fill the cistern?
In a stream running at 2 km/hr, a motor boat goes 10 km upstream and back again to the starting point in 55 minutes. Find the speed of the motorboat in still water ?
A cistern can be filled by two pipes filling separately in 12 and 16 min respectively. Both pipes are opened together for a certain time but being obstructions, only 7/8 of full quantity water flows through the former and only 5/6 through the latter pipe. The obstructions, however, being suddenly removed, the cistern is filled in 3 minutes from that moment. How long was it obstructions before the full flow began?
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?
Two pipes can fill a tank in 20 hrs and 24 hrs respectively. A third pipe can empty the tank in 40 hours. If all the three pipes are opened and function simultaneously. Then, in how much time the tank will be full?
Four pipes P, Q, R and S can fill a cistern in 25, 20, 50 and 40 hours respectively. The pipe Q was opened at 7 pm, P at 9 pm, S at 10 pm and R at 11 pm. When will the cistern be full?
A tap can fill the tank in 8 hours and another can empty it in 16 hours. If both the taps are opened simultaneously, the time (in hours) to fill the tank is__.
Three pipes, A B and C, can fill a cistern in 12, 18 and 24 minutes, respectively. If all the pipes are opened together for 7 minutes, what will be the volume of the water that overflows as the percentage of the total volume of the cistern?

Discussion

No Comment Found

Related MCQs

Reply to Comment