**Q1. A water tank normally takes 7 hours to be filled by a tap but because of the leak, it takes another 2 hours. In how many hours will the leak empty a full water tank? **

**Q2. A cistern can be filled separately by two pipes P and Q in 45 minutes and 35 minutes respectively. A tap R at the bottom can empty the full cistern in 30 minutes. If the tap R is opened 7 minutes after the two pipes P and Q are opened, then after what time from the opening of tap R the cistern becomes full?(Answer will be in approximate manner.) **

**Q3. Tap A fills a tank in 20 minutes while C empties it at 1/3rd the rate at which A fills it. At 12 : 00 noon, A and C are simultaneously started and when the tank is 50% full, tap A is turned off. At what time will the tank be empty? **

**Q4. Two pipes X and Y can fill a tank in 6 hours and 9 hours respectively. If they are turned on alternately for one hour each starting with X, then what is the time taken to fill the tank?**

**Q5. Four plumbers had to repair 364 taps. At the end of 3 days working 7 hours per day they had repaired 168 taps. In order to speed up the work, 3 more plumbers were added who also worked 7 hours daily. If efficiency of each of the plumbers is same, how many additional days would it take to complete the task? **

**Q6. Pipe A and B can fill a cistern in 10 hours and 15 hours respectively. When a third pipe C which works as an outlet pipe is also open then the cistern can be filled in 18 hours. The outlet pipe can empty a full cistern in :**

**Directions (7-10) : Read the following data and answer the questions that follow. A set of 10 pipes (set X) can fill 70% of a tank in 7 minutes. Another set of 6 pipes (set Y) fills 3/8 of the tank in 3 minutes. A third set of 8 pipes (set Z) can empty 5/10 of the tank in 10 minutes. **

**Q7. How many minutes will it take to fill the tank if all the 24 pipes are opened at the same time?**

**Q8. If only half the pipes of set X are opened and half the pipes of set Y are opened and all other pipes of set Z are opened, approximately how long will it take to fill 49% of the tank? **

**Q9. If 4 pipes are closed in set Z, and all other remain open, how long will it take to fill the tank?**

**Q10. If the tank is half filled and set X and Y are closed, how many minutes will it take for set Z to empty the tank. **

**Q11. There are two taps to fill a tank and a third to empty it. When the third tap is closed, they can fill the tank in 10 min and 12 min, respectively. If all the three taps be opened, the tank is filled in 15 min. If the first two taps are closed, in approximately what time can the third tap empty the when it is full? **

**Q12. Tap A can fill a tank in 20 hours, B in 25 hours but tap C can empty a full tank in 30 hours. Starting with A, followed by B and C each tap opens alternatively for one hour period till the tank gets filled up completely. In how many hour the tank will be filled up completely? **

**Q13. Two pipes A and B can fill a cistern in 15 hours and 10 hours respectively. A tap C can empty the full cistern in 30 hours. All the three taps were open for 2 hours, when it was remembered that the emptying tap had been left open. It was then closed. How many hours more would it take for the cistern to be filled? (relative to the case where the emptying tap was closed before opening the filling pipes A and B)**

**Q14. A water tank has three taps A, B and C. A fills four buckets in 24 minutes, B fills 8 buckets in 1 hour and C fills 2 buckets in 20 minutes. If all the taps are opened together a full tank is emptied in 2 hours. If a bucket can hold 5 liters of water, what is the capacity of the tank? (Taps can be used inlet as well as outlet.)**

**Q15. Pipe A can fill an empty tank in 30 hours while B can fill it 45 hours. Pipe A and B are opened and closed alternatively i.e., first pipe A is opened, then B, again A and then B and so on for 1 hour each time without any time lapse. In how many hours the tank will be filled when it was empty, initially ? **