51). Two pipes A and B can fill a tank in 1 h and 75 min, respectively. There is also an outlet C. If all the three pipes are opened together. The tank is full in 50 min. How much time will be taken by C to empty the full tank?
A). 100 min 
B). 150 min 
C). 200 min 
D). 125 min 

52). A tank has a leak which would empty it in 8 h. A tap is turned on which admits 3 L a min into the tank and it is now emptied in 12 h. How many litres does the tank hold?
A). 4320 L 
B). 4000 L 
C). 2250 L 
D). 4120 L 

53). A, B and C are three pipes connected to a tank. A and B together fill the tank in 6 h, B and C together fill the tank in 10 h and A and C together fill the tank in 12 h. In how much time A, B and C fill up the tank together?
A). 9 h 
B). \( \Large 5\frac{3}{7} \) h 
C). \( \Large 5\frac{2}{7} \) h 
D). \( \Large 5\frac{5}{7} \) h 

54). Two pipes A and B are opened together to fill a tank. Both pipes fill the tank in a certain time. If A separately takes 16 min more than the time taken by (A + B) and B takes 9 min more than the time taken by (A + B). Find the time taken by A and B to fill the tank when both the pipes are opened together.
A). 10 min 
B). 12 min 
C). 15 min 
D). 8 min 

55). Two pipes can fill a tank in 20 and 24 min, respectively and a waste pipe can empty 6 gallon per min. All the three pipes working together can fill the tank in 15 min. Find the capacity of the tank.
A). 210 gallon 
B). 50 gallon 
C). 150 gallon 
D). 240 gallon 

56). Inlet A is four times faster than inlet B to fill a tank. If A alone can fill it in 15 min, how long will it take if both the pipes are opened together?
A). 10 min 
B). 12 min 
C). 15 min 
D). 14 min 

57). There are two inlets A and B connected to a tank. A and B can fill the tank in 16 h and 10 h, respectively. If both the pipes are opened alternately for 1 h, starting from A, then how much time will the tank take to be filled?
A). \( \Large 13\frac{1}{4} \) 
B). \( \Large 11\frac{6}{8} \) 
C). \( \Large 12\frac{2}{5} \) 
D). \( \Large 12\frac{1}{4} \) 

58). Two pipes X and Y can fill a cistern in 6 and 7 min, respectively. Starting with pipe X, both the pipes are opened alternately, each for 1 min. In what time will they fill the cistern?
A). \( \Large 6\frac{2}{7} \) 
B). \( \Large 6\frac{3}{7} \) 
C). \( \Large 6\frac{5}{7} \) 
D). \( \Large 6\frac{1}{7} \) 

59). A tap having diameter 'd' an empty a tank in 40 min. How long another tap having diameter '2d' take to empty the same tank?
A). 5 min 
B). 29 min 
C). 10 min 
D). 40 min 

60). Two pipes can fill a cistern in 14 and 16 h, respectively. The pipes are opened simultaneously and it is found that due to leakage in the bottom, it took 92 min more to fill the cistern. When the cistern is full, in what time will the leak empty it?
A). \( \Large 43\frac{19}{23} \) h 
B). \( \Large 43\frac{17}{23} \) h 
C). \( \Large 43\frac{13}{23} \) h 
D). \( \Large 43\frac{15}{23} \) h 
