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Cover image for Top 10 Most Important Pipes & Cistern Aptitude Problems.
Piyush Kumar Singh
Piyush Kumar Singh

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Top 10 Most Important Pipes & Cistern Aptitude Problems.

Reference : Pipes & Cistern

Q1. A pipe can fill a tank in 12 hours, and another pipe can empty the same tank in 15 hours. If both pipes are opened simultaneously, in how many hours will the tank be filled?
80 hours
72 hours
54 hours
60 hours

Q2. Three pipes A, B, and C can fill a tank in 6, 8, and 12 hours respectively. If all pipes are opened simultaneously, how long will they take to fill the tank?
2.7 hours
3.6 hours
3 hours
2.4 hours

Q3. A tank has two inlet pipes and one outlet pipe. The first inlet pipe fills the tank in 5 hours, the second inlet pipe fills the tank in 7 hours, and the outlet pipe empties the tank in 10 hours. If all pipes are opened simultaneously, in how many hours will the tank be filled?
3.9 hours
4.2 hours
2.8 hours
3.5 hours

Q4. A cistern has two pipes. One pipe can fill the tank in 6 hours, while another can empty it in 4 hours. If the tank is initially empty and both pipes are opened simultaneously for 2 hours, what fraction of the tank will be filled?
3/4
1/2
2/3
1/3

Q5. Three pipes A, B, and C can fill a tank in 12, 15, and 20 hours respectively. If pipe A is closed after 3 hours and pipes B and C continue to fill the tank, how long will it take to completely fill the tank?
8 hours
7.2 hours
5.4 hours
6.5 hours

Q6. A tank can be filled by three pipes of different diameters. The first pipe fills the tank in 10 hours, the second in 15 hours, and the third in 20 hours. What is the time taken to fill the tank if all pipes are opened together?
5.5 hours
4.5 hours
5 hours
4 hours

Q7. A tank can be filled by two pipes. If the first pipe is used, it takes 12 hours to fill the tank. If the second pipe is used, it takes 15 hours. How long will it take to fill the tank if the pipes are used alternately for 1 hour each?
12 hours
10 hours
11 hours
9 hours

Q8. A tank has a leak which can empty the full tank in 8 hours. An inlet pipe can fill the tank in 6 hours. If both the inlet pipe and leak are open, the tank will be filled in 12 hours. How much of the tank does the leak empty per hour?
1/6 tank/hour
1/10 tank/hour
1/8 tank/hour
1/12 tank/hour

Q9. A tank has three pipes. The first pipe fills the tank in 14 hours, the second in 10 hours, and the third empties the tank in 35 hours. If all pipes are opened simultaneously, in how many hours will the tank be filled?
10 hours
8 hours
9 hours
7 hours

Q10. Two pipes can fill a tank in 12 and 15 hours respectively. If the first pipe is opened for 4 hours and then the second pipe is opened, how long will it take to fill the remaining part of the tank?
6 hours
10 hours
5.6 hours
4.8 hours

Other References :

AP & GP : Link
Area : Link
Average : Link
Boat & Stream : Link
Compound Interest : Link
Height & Distance : Link
LCM & HCF : Link
Logarithm : Link
Percentage : Link
Profit & Loss : Link
Ratio & Proportion : Link
Simple Interest : Link
Speed Distance : Link
Time & Work : Link
Trains Problem : Link

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