Bank Exams Exam  >  Bank Exams Notes  >  IBPS PO Prelims & Mains Preparation  >  Pipes and Cisterns - Concepts and Tricks

Pipes and Cisterns - Concepts and Tricks | IBPS PO Prelims & Mains Preparation - Bank Exams PDF Download

Introduction

Competitive exams consistently feature questions on pipes and cisterns. Typically, problem-solving in this category involves applying methods related to work and time. These questions are often presented as word problems during competitive examinations, employing concepts akin to those used in work and time problems.

The basic structure of these types of questions is,

  • A tank has to be filled or emptied by two or more pipes
  • Time taken by each pipe to fill or empty the tank is given or should be found
  • Total time taken to fill or empty the tank is given or should be found

Pipes

Pipes are conduits linked to tanks for either filling or draining liquids. Tanks, alternatively termed cisterns or reservoirs, are the containers in question. Consequently, the inquiries revolve around the effectiveness of pipes in the processes of tank filling or emptying.

There are two types of pipes:

  • Inlet Pipe: As the name implies, these pipes are employed to introduce or deliver liquid into the tank. In simpler terms, inlet pipes facilitate the filling of tanks.

  • Outlet Pipe: As the name implies, these pipes are utilized to discharge or expel liquid from the tank. In simpler terms, outlet pipes facilitate the emptying of tanks. They may also be referred to as leaks.
    Pipes and Cisterns - Concepts and Tricks | IBPS PO Prelims & Mains Preparation - Bank Exams

Formulae and Short Tricks

Here are some formulas and brief techniques for solving problems related to pipes and cisterns:

Formula 1:

If pipe A can completely fill a tank in x hours, then the portion filled in 1 hour is . (or) If pipe A fills 1/x portion of the tank in 1 hour, then the time taken by the pipe to fill the full tank is x hours.

Example: If a pipe fully fills a tank in 10 hours, what part of the tank will be filled by the pipe in 1 hour?
Sol:
According to the above given formula, if pipe can comletely fill a tank in x hours, then the portion filled in 1 hour is 1/x
Hence, 1/10th part of the tank will be filled by the pipe in 1 hour.

Formula 2: 

If pipe A can completely empty a tank in y hours, then the portion emptied in 1 hour is 1/y (or) If pipe A empties 1/y portion of the tank in 1 hour, then the time taken by the pipe to empty the full tank is y hours.

Example: If an outlet pipe can empty a cistern in 15 hours, in what what time can the pipe empty 3/5 of the cistern?

Sol: According to the above given formula, if pipe can comletely empty a tank in y hours, then the portion emptied in 1 hour is 1/y
so, Pipes and Cisterns - Concepts and Tricks | IBPS PO Prelims & Mains Preparation - Bank ExamsHence, 3/5 th part of the tank will be emptied by the pipe in 9 hours.

Formula 3: 

If pipe A fills a tank in x hours and another pipe B fills a tank in y hours, then the time taken by both pipes together to fill the tank is Pipes and Cisterns - Concepts and Tricks | IBPS PO Prelims & Mains Preparation - Bank Examshours.

Example: If a pipe can fill a tank in 2 hours and another pipe can fill the same tank in 8 hours, then what part of the tank can be filled by both the pipes when opened simultaneously?
Sol: According to the above given formula, if pipe A can comletely fill a tank in x hours and pipe B can comletely fill a tank in y hours, then the time taken by both pipes together to fill the tank is Pipes and Cisterns - Concepts and Tricks | IBPS PO Prelims & Mains Preparation - Bank Examshours.

Pipes and Cisterns - Concepts and Tricks | IBPS PO Prelims & Mains Preparation - Bank ExamsHence, 8/5th part of the tank will be filled by both the pipe when opened simultaneously.

Pipes And Cistern - MCQ 1
Start Test
Start Test

Formula 4: 

If pipe A fills a tank in x hours and another pipe B empties the tank in y hours (where y>x), then the time taken to fill the tank when both the pipes are open is Pipes and Cisterns - Concepts and Tricks | IBPS PO Prelims & Mains Preparation - Bank Exams hours.

Example: If a pipe can fill a tank in 5 hours and another pipe can empty the same tank in 7 hours. If both the pipes are opened simultaneously, how much time will be taken to fill the tank?
Sol: According to the above given formula, if pipe A can comletely fill a tank in x hours and pipe B can empty the same tank in y hours, then the time taken to fill the tank when both the pipes are opened simultaneously is Pipes and Cisterns - Concepts and Tricks | IBPS PO Prelims & Mains Preparation - Bank Exams hours.Pipes and Cisterns - Concepts and Tricks | IBPS PO Prelims & Mains Preparation - Bank ExamsHence, the tank will be filled in 17.5 hours when both the pipes are opened simultaneously.

Formula 5: 

If pipe A fills a tank in x hours and another pipe B empties the tank in y hours (where x>y), then the time taken to fill the tank when both the pipes are open is Pipes and Cisterns - Concepts and Tricks | IBPS PO Prelims & Mains Preparation - Bank Exams hours.

Example: If a pipe can fill a tank in 15 hours and another pipe can empty the same tank in 8 hours. If both the pipes are opened simultaneously, how much time will be taken to fill the tank?

Sol: According to the above given formula, if pipe A can comletely fill a tank in x hours and pipe B can empty the same tank in y hours, then the time taken to fill the tank when both the pipes are opened simultaneously is Pipes and Cisterns - Concepts and Tricks | IBPS PO Prelims & Mains Preparation - Bank Exams hours.Pipes and Cisterns - Concepts and Tricks | IBPS PO Prelims & Mains Preparation - Bank ExamsHence, the tank will be filled in 17.14 hours when both the pipes are opened simultaneously.

Formula 6: 

If three pipes A, B and C can fill the tank separately in x hours, y hours and z hours respectively then, the time taken by all the three pipes together to fill the tank is Pipes and Cisterns - Concepts and Tricks | IBPS PO Prelims & Mains Preparation - Bank Exams hours.

Example: Three pipes x, y, z fill a tank in 4, 5, and 6 hours respectively. The time taken by all the three pipes to fill the tank when opened simultaneously is?
Sol: According to the above given formula, If three pipes A, B and C can fill the tank separately in x hours, y hours and z hours respectively then, the time taken by all the three pipes together to fill the tank is Pipes and Cisterns - Concepts and Tricks | IBPS PO Prelims & Mains Preparation - Bank Exams hours.So,Pipes and Cisterns - Concepts and Tricks | IBPS PO Prelims & Mains Preparation - Bank ExamsHence, the tank will be filled in Pipes and Cisterns - Concepts and Tricks | IBPS PO Prelims & Mains Preparation - Bank Exams hours when all the pipes are opened simultaneously.

Formula 7: 

If pipe A  and B fills a tank in x and y hours respectively, but a third pipe C empties the full tank in z hours then the net portion filled in 1 hour when all of them are opened together is Pipes and Cisterns - Concepts and Tricks | IBPS PO Prelims & Mains Preparation - Bank Exams hours.

Example: Two pipes x, y fill a tank in 20, 10 hours respectively. The third pipe z empties the full tank in 30 hours. If all the three are opened simultaneously, how much time will be required to fill the tank? 
Sol: According to the above given formula, If pipe A and B fills a tank in x and y hours respectively, but a third pipe C empties the full tank in z hours then the net portion filled in 1 hour when all of them are opened together is Pipes and Cisterns - Concepts and Tricks | IBPS PO Prelims & Mains Preparation - Bank Exams hours.So, Pipes and Cisterns - Concepts and Tricks | IBPS PO Prelims & Mains Preparation - Bank ExamsHence, the tank will be filled in Pipes and Cisterns - Concepts and Tricks | IBPS PO Prelims & Mains Preparation - Bank Exams hours when all the pipes are opened simultaneously.

Formula 8: 

Two pipes A and B can fill the tank in x and y min respectively. If both pipes are opened together, then the time after which pipe B should be closed so that the tank is full in t min is Pipes and Cisterns - Concepts and Tricks | IBPS PO Prelims & Mains Preparation - Bank Examsmin.

Example: Two pipes m and n can fill a tank in 12, 6 min respectively. If both the pipes are opened simultaneously, after how much time should pipe n be closed so that the tank is full in 4 min? 

Sol: According to the above given formula, If Two pipes A and B can fill the tank in x and y min respectively. If both pipes are opened together, then the time after which pipe B should be closed so that the tank is full in t min is Pipes and Cisterns - Concepts and Tricks | IBPS PO Prelims & Mains Preparation - Bank Exams min.Pipes and Cisterns - Concepts and Tricks | IBPS PO Prelims & Mains Preparation - Bank Exams

Hence, the tank will be filled in 4 min both the pipes are opened simultaneously.

Download the notes
Pipes and Cisterns - Concepts and Tricks
Download as PDF
Download as PDF

Formula 9: 

Two pipes A and B can together fill a tank in time T. If time taken by pipe A alone is more than T by x and the time taken by pipe B alone is more than T by y, then T is

Pipes and Cisterns - Concepts and Tricks | IBPS PO Prelims & Mains Preparation - Bank Exams min.Pipes and Cisterns - Concepts and Tricks | IBPS PO Prelims & Mains Preparation - Bank ExamsHence, the tank will be completely filled in 8 min.

Formula 10: 

Suppose we have many pipes, where some fill the tank and some empty the tank. If we open all of them together, then in one hour, 

  • the part of the tank filled is ∑ (1 / xi) + ∑ (1 / yo)
  • the part of the tank emptied is ∑ (1 / xi) - ∑ (1 / yo)

where ‘xi‘ is the time taken by inlet pipe ‘i’ to fill the tank completely if only it was open and ‘yo‘ is the time taken by outlet pipe ‘o’ to empty the tank completely if only it was open.

 

The document Pipes and Cisterns - Concepts and Tricks | IBPS PO Prelims & Mains Preparation - Bank Exams is a part of the Bank Exams Course IBPS PO Prelims & Mains Preparation.
All you need of Bank Exams at this link: Bank Exams
Are you preparing for Bank Exams Exam? Then you should check out the best video lectures, notes, free mock test series, crash course and much more provided by EduRev. You also get your detailed analysis and report cards along with 24x7 doubt solving for you to excel in Bank Exams exam. So join EduRev now and revolutionise the way you learn!
Sign up for Free Download App for Free
541 videos|681 docs|263 tests

Up next

FAQs on Pipes and Cisterns - Concepts and Tricks - IBPS PO Prelims & Mains Preparation - Bank Exams

1. What are the basic concepts of pipes and cisterns?
Ans. Pipes and cisterns is a mathematical topic that deals with the calculation of water flow rates, filling or emptying of tanks, and the time taken to fill or empty them. It involves understanding the relationship between the rate of water flow, the capacity of pipes or cisterns, and the time required to fill or empty them.
2. How do you solve problems related to pipes and cisterns in banking exams?
Ans. To solve problems related to pipes and cisterns in banking exams, you need to understand the basic concepts and formulas involved. You should be able to calculate the individual rates of different pipes, determine their combined rate when working together, and use this information to find the time taken to fill or empty a cistern. Practice solving different types of problems to improve your speed and accuracy.
3. What are the common tricks or shortcuts to solve pipes and cisterns problems quickly?
Ans. Here are some common tricks or shortcuts to solve pipes and cisterns problems quickly: - Use the concept of efficiency: If a pipe fills a tank in x hours, its efficiency is 1/x. Similarly, if a pipe empties a tank in x hours, its efficiency is -1/x. - When pipes work together, add their individual efficiencies to find the combined efficiency. - When pipes work against each other, subtract their individual efficiencies to find the net efficiency. - Use the concept of LCM (Least Common Multiple) to find the time taken to fill or empty the tank. - Use the formula: Time = Volume / Efficiency to find the time taken.
4. Can you provide an example problem related to pipes and cisterns?
Ans. Sure, here's an example problem: If Pipe A can fill a tank in 8 hours and Pipe B can empty the same tank in 12 hours, how long will it take to fill the tank if both pipes are open together? Solution: The efficiency of Pipe A = 1/8 The efficiency of Pipe B = -1/12 Combined efficiency = 1/8 - 1/12 = 1/24 Time taken = Volume / Combined efficiency Let's assume the volume of the tank is 24 liters (a common multiple of 8 and 12). Time taken = 24 / (1/24) = 24 * 24 = 576 hours. Therefore, it will take 576 hours to fill the tank if both pipes A and B are open together.
5. How can I improve my speed and accuracy in solving pipes and cisterns problems for banking exams?
Ans. To improve your speed and accuracy in solving pipes and cisterns problems for banking exams, you can: - Practice solving a variety of problems regularly to familiarize yourself with different problem types and techniques. - Memorize the common formulas and shortcuts related to pipes and cisterns. - Take timed mock tests or solve practice papers to simulate the exam environment and improve your speed. - Analyze your mistakes and learn from them. Understand where you went wrong and find ways to avoid similar errors in the future. - Seek guidance from teachers or mentors who can provide tips and strategies to solve pipes and cisterns problems more efficiently.
541 videos|681 docs|263 tests
Download as PDF

Up next

Explore Courses for Bank Exams exam
Related Searches

Sample Paper

,

Pipes and Cisterns - Concepts and Tricks | IBPS PO Prelims & Mains Preparation - Bank Exams

,

mock tests for examination

,

past year papers

,

Previous Year Questions with Solutions

,

Pipes and Cisterns - Concepts and Tricks | IBPS PO Prelims & Mains Preparation - Bank Exams

,

pdf

,

Viva Questions

,

Summary

,

Objective type Questions

,

Important questions

,

Free

,

ppt

,

Exam

,

study material

,

Extra Questions

,

Pipes and Cisterns - Concepts and Tricks | IBPS PO Prelims & Mains Preparation - Bank Exams

,

MCQs

,

video lectures

,

practice quizzes

,

shortcuts and tricks

,

Semester Notes

;