1. Acan fill the tank in 30 min and B can fill the tank in 45 min. Find the time taken by both working together to fill the tank completely.
A) 27 min B) 20 min C) 12 min D) 9 min E) 18 min
2. Pipe P and Q can fill a tank in 28 minutes and 42 minutes respectively, if these pipes are opened for 14 minutes after pipe P was closed pipe Q fills the remaining tank. Find the time taken by Q to fill the remaining tank. (In min.)
A) 7 B) 14 C) 12 D) 4 E) 9
3. Pipes M can fill a tank X in 30 mins and pipe N can fill a tank Y in 50 mins. If the capacities of both tanks X and Y are 3 : 4, then find the time taken by both pipes can fill the tank X. (in min.)
A) 
B) 
C) 
D) 
E) 
4. Three pipes A, B and C can fill a cistern in 10, 15, and 20 minutes, respectively. If all the pipes are opened together for 6 minutes, then the extra volume of water flow is (x + 7)% of the total volume of the cistern. Find the value of x% of 3200.
A) 636 B) 736 C) 786 D) 756 E) 796
5. Two pipes P and Q can fill a tank in 12 hrs and 20 hrs respectively and pipe R alone can empty the tank in 30 hrs, and then find the time by three pipes opened together to fill 
rd of the empty tank?
A) 6 hrs B) 5 hrs 45 mins C) 7 hrs 30 mins D) 6 hrs 40 mins E) 5 hrs 30 mins
6. Two pipes M and N Two pipes M and N can fill the tank in 42 min and 70 min respectively and X can empty the tank in 30 min. If all three pipes are opened together, how much time will it take to empty or fill the tank? (in hrs)
A) 3.5 hrs B) 1.5 hrs C) 1 hr D) 1.75 hrs E) 2 hrs
7. Two pipes Aand B can fill a tank in 360 min and 480 min respectively. If they are turned on alternately for 60 min each starting with B, what amount of time is taken by them to fill the tank?
A) 6.75 hrs B) 7 hrs C) 4 hrs D) 3.75 hrs E) 13 hrs
8. Two pipes A and B can fill together a tank in 16 minutes and 14 minutes respectively. If both pipes are opened together and after 4 minutes pipe A is closed, find the total time in which the tank will be filled.
A) 
B) 
C) 
D) 14 E) 
9. Pipe X and Y alone can fill a tank in 25 minutes and 30 minutes, respectively pipe Z can empty the tank in 50 minutes. Pipe X and Y opened from the beginning and after 10 minutes pipe Z was also opened. In how much time tank will be filled?
A) 13 mins B) 12 mins C) 15 mins D) 5 mins E) 10 mins
10. Two pipes independently can fill a tank in 16 hours and 24 hours respectively. However, due to leakage in the tank it took 24 minutes more to fill the tank when both the pipes were opened simultaneously. When the tank is full, in how much time will the leakage empty it? (In hours)
A) 240 B) 200 C) 180 D) 280 E) 220
11. A tank has 3 inlets A, B and C which take 
hour to fill the tank when they are opened simultaneously. If C alone takes twice the time taken by B to fill the tank alone and A alone takes 
the time taken by B to fill the tank alone, how much time will C alone take to fill the tank independently?
A) 10 hours B) 
hours C) 20 hours D) 
hours E) 
hours
12. Three pipes A and B can fill the tank in 16 minutes and 48 minutes respectively.Another pipe C alone can empty the whole tank in 24 minutes. Initially pipes A and B were opened together for 5 minutes, then pipe C was also opened, then find how many minutes will they take to fill the tank.
A) 15 B) 14 C) 19 D) 13 E) 16
Key
1-E ; 2-A ; 3-A ; 4-B ; 5-D ; 6-A ; 7-B ; 8-A ; 9-D ; 10-A ; 11-C ; 12-C
