Pipe and Cistern Questions and Answers for Competitive Exams
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) 22 km/hr
(B) 24 km/hr
(C) 26 km/hr
(D) 20 km/hr
(E) 28 km/hr
Correct Answer : A
Two pipes A and B can fill a tank in 24 min and 27 min respectively. If both the pipes are opened simultaneously, after how much time should B be closed so that the tank is full in 16 minutes?
(A) 8 min
(B) 10 min
(C) 12 min
(D) 9 min
(E) 14 min
Correct Answer : D
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?
(A) 10 hrs
(B) 15 hrs
(C) 16 hrs
(D) 12 hrs
(E) 18hrs
Correct Answer : B
One filling pipe P is three times faster than another filling pipe Q, if P can fill tank in 24 hours, then what is the time taken to completely fill the tank if both the pipes are opened together?
(A) 12 hours
(B) 18 hours
(C) 16 hours
(D) 14 hours
(E) None of these
Correct Answer : B
Two pipe A and B can fill a tank in 16 hrs and 12 hrs respectively. The capacity of the tank is 240 litres. Both the pipes are opened simultaneously and closed after 2 hrs. How much more water (In Liters) needed to fill the tank?
(A) 100
(B) 170
(C) 70
(D) 190
(E) None of these
Correct Answer : B
A tank can be filled with water by two pipes A and B together in 36 minutes. If the pipe B was closed after 30 minutes, the tank is filled in 40 minutes. The pipe B can alone fill the tank in?
(A) 45 minutes
(B) 60 minutes
(C) 75 minutes
(D) 90 minutes
(E) 85 minutes
Correct Answer : D
Pipe A alone & pipe B alone can fill the same tank in 5 hours and 4 hours respectively. If the ratio of efficiency of pipe A & B together to that of pipe C alone is 9:2, then find time taken by pipe C alone to fill the same tank?
(A) 8 hours
(B) 5 hours
(C) 6 hours
(D) 10 hours
Correct Answer : D
A cistern has 3 pipes A, B and C. A and B can fill it in 3 and 4 hours respectively, and C can empty it in 1 hour. If the pipes are opened at 3 p.m., 4 p.m. and 5 p.m. respectively on the same day, the cistern will be empty at-
(A) 7.12 p.m.
(B) 7.15 p.m.
(C) 7.10 p.m.
(D) 7.18 p.m.
Correct Answer : A
A pipe of diameter ‘d’ can drain a certain water tank in 40 minutes. The time taken by a pipe of diameter ‘2d’ for doing the same job in:
(A) 5 minutes
(B) 10 minutes
(C) 20 minutes
(D) 80 minutes
Correct Answer : B
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?
(A) 4 hrs
(B) 4 hrs15 min
(C) 3 hrs 15 min
(D) 3 hrs 45 min
Correct Answer : D