Top 130 Pipe and cistern questions for Competitive Exams [ 100% FREE ]

Introducing an important aspect of the quantitative aptitude section: the Pipe and cistern questions. A common challenge candidates face in various competitive exams, be it banks, SSC, RRB, Insurance and more, is problems related to pipes and cisterns. In this comprehensive article, we delve deep into “Pipe and cistern questions“, ensuring you get the most effective preparation material.

For many, the term “Pipe and cistern questions” can seem daunting, but with the right approach and understanding of the “pipes and cisterns formula“, it becomes manageable. This is why we’re emphasizing on the crucial examples like “two pipes p and q together can fill a cistern” and “two pipes a and b can fill a cistern“. Both these examples will give you a clear perspective on how to approach these problems.

We also recognize the importance of language adaptability in preparation. Therefore, we have also incorporated “pipe and cistern questions in Hindi” and insights on “pipe and cistern in Hindi“. This ensures that you not only understand the crux of the “pipes and cisterns problems” but also can relate to them in a language you’re comfortable with.

Word problems, especially around the “pipes and cisterns formula“, have been a mainstay in competitive exams. While “two pipes p and q together can fill a cistern” or “two pipes a and b can fill a cistern” might seem similar, they can carry nuances that are essential for aspirants to grasp.

Pipes and Cisterns Formula :

Given below are aimportant formulas which shall help you solve the pipes and cistern based questions quicker and more efficiently:

  • If x hours are required to fill up a tank, then part filled in 1 hr =1/x
  • If y hours are required to empty the tank, then part emptied in 1 hour = 1/y
  • If a pipe can fill a tank in x hours and can empty the same tank in y hours. When both the pipes are opened at the same time, then the net part of the tank filled in 1 hr = {(xy) / (y-x)}, provided y>x
  • If a pipe can fill a tank in x hours and can empty the same tank in y hours. When both the pipes are opened at the same time, then the net part of the tank filled in 1 hr = {(xy) / (x-y)}, provided x>y
  • Net work done = (Sum of work done by Inlets) – (Sum of work done by Outlets)
  • One inlet can fill the tank in x hr and the other inlet can fill the same tank in y hrs, if both the inlets are opened at the same time, the time taken to fill the whole tank = {(xy) / (y+x)}
  • If two pipes take x and y hours respectively to fill a tank of water and a third pipe is opened which takes z hours to empty the tank, then the time taken to fill the tank = {1 / (1/x)+(1/y)+(1/z)} and the net part of the tank filled in 1 hr = (1/x)+(1/y)-(1/z)

The syllabus for competitive exams is vast, as we all know. But every topic, including “Pipe and cistern questions“, holds its weight. Therefore, giving due time to understand and practice these “pipes and cisterns problems” is paramount. Especially when considering the intense competition and the challenge to crack these exams.

In conclusion, this article offers an in-depth understanding of “Pipe and cistern questions“, covering essential examples like “two pipes p and q together can fill a cistern” and “two pipes a and b can fill a cistern“, not forgetting the importance of language with “pipe and cistern questions in Hindi” and “pipe and cistern in Hindi“.

Whether you’re just starting out or brushing up your skills, this article is your guide to excel. So, gear up and dive into the world of “Pipe and cistern questions” and ace your upcoming Government sector exams!

Top 130 Pipe and cistern questions for Competitive Exams :

61. Pipe P can fill the cistern X in 25 minutes, Pipe Q is opened in cistern Y and after 5 minutes P is allowed inside cistern Y to fill it, after 35 minutes cistern gets filled, then find the time taken by the Pipe Q alone to fill cistern X if capacity of cistern Y is thrice the capacity of cistern X?

पाइप P अकेले 25 मिनट में टैंक X को भर सकता है, पाइप Q को टैंक Y में खोला जाता है और 5 मिनट के बाद P को भी टैंक Y के अंदर भरने की अनुमति दी जाती है, 35 मिनट के बाद टैंक भर जाती है, फिर पाइप Q द्वारा अकेले टैंक X को भरने में लगने वाला समय ज्ञात करें, यदि टैंक Y की क्षमता टैंक X की तिगुनी है?

A. 15 minutes
B. 20 minutes
C. 25 minutes
D. 30 minutes
E. 40 minutes

Option “C” is correct.

Pipe P can fill cistern X in 25 minutes,

Capacity of cistern Y is thrice of X, therefore time taken by Pipe P to fill cistern Y is 3*25=75 minutes

To fill cistern Y ,Pipe Q is opened for 40 minutes and P opened for 35 minutes

Q=75 minutes

Pipe Q alone fill the cistern Y in 75 minutes, therefore it takes 75/3 =25 minutes to fill cistern X.

62. Pipe X and Y can fill the cistern in 60 minutes and 1.5 hours respectively, then What is the total time taken to fill the tank completely by 80%, if pipes are opened alternatively starting with X, also X and Y opened at 75% and 90% of its efficiency.

पाइप X और Y क्रमशः 60 मिनट और 1.5 घंटे में टैंक को भर सकते हैं, फिर टैंक को पूर्णतया 80% तक भरने में लिया गया कुल समय क्या है, यदि पाइप को X से शुरू करते हुए वैकल्पिक रूप से खोला गया है, साथ ही X और Y अपनी दक्षता के 75% और 90% पर खोले गए हैं।

A. 72 minutes
B. 71 minutes
C. 70 minutes
D. 74 minutes
E. 73 minutes

Option “B” is correct.

Time taken by Pipe X to fill when working at 75% of its efficiency

= (100/75) * (60) =80minutes

Time taken by Pipe Y to fill when working at 90% of its efficiency

= (100/90) * (90) =100 minutes

Let time taken to fill 80% of tank be ‘x’

Total units of work 400

A did 5 units per minute, B did 4 units per minute

For every 2 minutes, 9 units of work is completed by them.

At the end of 70th minute 315 units are completed, at 71st minute A did 5 units (315+5=320 i.e 80% of the work)

63. Pipes X and Y fill the cistern P in 12 and 20 hours respectively. If capacity of cistern Q is twice the capacity of cistern P, then find the time taken by the pipes X and Y together to fill the cistern Q?

पाइप X और Y टैंक P को क्रमशः 12 और 20 घंटे में भर सकते हैं। यदि टैंक Q की क्षमता टैंक P की क्षमता से दोगुनी है, फिर पाइप X और Y द्वारा एक साथ टैंक Q को भरने में लगने वाला समय ज्ञात कीजिए?

A. 16 hours
B. 12 hours
C. 14 hours
D. 15 hours
E. 11 hours

Option “D” is correct.

Time taken by Pipes X and Y to fill cistern Q= 2(time taken by pipes X and Y to fill the cistern P)

Time taken by the pipes together to fill cistern

= (1/12)+(1/20)

= 32/240

= 7.5 hours

Therefore, time taken by pipes X and Y together to fill cisternQ = 2× =2(7.5)

= 15 hours

64. If the ratio of volume of cylindrical cistern A and B is 3:4, pipe x fill the cistern A in 90 hours, then find the time taken by pipe x to fill the cistern B if cistern B can have 1800 liters more than cistern A.

यदि बेलनाकार टैंक A और B के आयतन का अनुपात 3: 4 है, पाइप x टैंक A को 90 घंटों में भरता है, फिर पाइप x के द्वारा टैंक B को भरने में लिए गए समय को ज्ञात कीजिए, यदि टैंक B, टैंक A की तुलना में 1800 लीटर अधिक ले सकता है।

A. 90 hours
B. 100 hours
C. 120 hours
D. 150 liters
E. Can’t be determined

Option “C” is correct.

Let volume of cylinder A =3x

Volume of cylinder B =4x

Difference between volume of cylinders =1800

4x -3x =1800

x =1800 liters

Volume of cylinder A =3x = 5400 liters

Volume of cylinder B =4x = 7200 liters

Efficiency pipe x = 5400/90 = 60 liters/hour

Pipe x fills 60liters/hour

Required time = 7200/60 = 120 hours

65. Pipe A and B alone fill the tank in 15 hours and 20 hours respectively. If both pipes are opened simultaneously, after x hours pipe A is closed so that the tank take extra 2 hours and 30 minutes for fulfill the tank. Find the value of x?

पाइप A और B अकेले टैंक को क्रमशः 15 घंटे और 20 घंटे में भरते हैं। यदि दोनों पाइपों को साथ-साथ खोला गया है, फिर x घंटों के बाद पाइप A को बंद कर दिया गया है इस तरह से कि पाइप B, टैंक को पूरा भरने में 2 घंटे और 30 मिनट का अतिरिक्त समय लेता है। x का मान ज्ञात कीजिए?

A. 8 hours
B. 10 hours
C. 6 hours
D. 12 hours
E. None of these

Option “E” is correct.

x/15 + (x + 2.5)/20 = 1

4x + 3x + 7.5 = 60

x = 7.5 hours

66. Pipe X alone can fill the tank in 24 hours and the efficiency of pipe Y is 33.33% less than that of pipe X. Pipe X, Y and Z together can fill the tank in 72 hours. Pipe X, Y and Z are opened simultaneously and after K hours pipe Z is closed and the remaining tank is filled by pipe X and Y in 11 hours. Then find the value of K?

पाइप X अकेले टैंक को 24 घंटे में भर सकता है और पाइप Y की दक्षता, पाइप X की तुलना में 33.33% कम है। पाइप X, Y और Z मिलकर टैंक को 72 घंटे में भर सकते हैं। पाइप X, Y और Z को एक साथ खोला जाता है और K घंटे के बाद पाइप Z को बंद कर दिया जाता है और शेष टैंक को पाइप X और Y द्वारा 11 घंटे में भर दिया जाता है। तो K का मान ज्ञात कीजिए?

A. 13
B. 17
C. 19
D. 15
E. None of these

Option “B” is correct.

Time taken by X to fill the tank=24 hours

Time taken by Y to fill the tank=24*3/2= 36 hours

Time taken by X, Y and Z together to fill the tank=72 hours

LCM 24, 36, 72 =72

1/24+1/36+1/Z=1/72

1/Z=(1-3-2)/72

1/Z=-4/72

1/Z=-1/18

Efficiency of X, Y and Z together for 1 hour = 3+2-4= 1 Unit/hour

Work done by X and Y together in 11 hours =5*11= 55 units

Required time=(72-55)/1=17 hours

67. Two outlet pipes X and Y together can empty a tank in ‘K’ minutes. If X and Y take 64 minutes and 36 minutes more than ‘K’ minutes respectively to empty the tank. Then X and Y together can empty 60% of the tank in how many minutes?

दो आउटलेट पाइप X और Y मिलकर एक टैंक को ‘K’ मिनट में खाली कर सकते हैं। यदि X और Y टैंक को खाली करने में क्रमशः ‘K’ मिनट से 64 मिनट और 36 मिनट अधिक लेते हैं। तो X और Y मिलकर 60% टैंक को कितने मिनट में खाली कर सकते हैं?

A. 26(4/5) minutes
B. 28(4/5) minutes
C. 28(6/5) minutes
D. 24(4/5) minutes
E. None of these

Option “B” is correct.

1/(K+64) + 1/(K+36) = 1/K

(2K+100)/(K2+64K+36K+2304) = 1/K

2K2+100K = K2+100K+2304

K2=2304

K=48 minutes (neglecting negative values)

Required time = (60/100) * 48 = 144/5 = 28(4/5) minutes

68. Pipe L and M can fill a tank in 10 minutes and 15 minutes respectively and Pipe N alone can empty the tank in x minutes and the ratio of the efficiency of Pipe L and N is 6:5. Find the total time taken to fill the tank, if all the pipes are opened together.

पाइप L और M एक टैंक को क्रमशः 10 मिनट और 15 मिनट में भर सकते हैं और अकेला पाइप N टैंक को x मिनट में खाली कर सकता है और पाइप L और N की दक्षता का अनुपात 6:5 है। यदि सभी पाइपों को एक साथ खोल दिया जाए तो टैंक को भरने में लगने वाला कुल समय ज्ञात कीजिए।

A. 10 minutes
B. 8 minutes
C. 12 minutes
D. 5 minutes
E. None of these

Option “C” is correct.

Ratio of time taken by Pipe L and N = 5:6

Pipe N alone can empty the tank in = 10 * 6/5 = 12 minutes

Total time taken = 1/10 + 1/15 – 1/12 = (6 + 4 – 5)/60 = 1/12 = 12 minutes

69. Pipe A, B and C together can fill a tank x minutes and Pipe A and Pipe B alone can fill the tank in x/4 minutes and x/5 minutes respectively. Pipe C alone can empty the tank in 10 minutes. Find the time taken by Pipe A alone to fill the tank.

एकसाथ पाइप A, B और C एक टैंक को x मिनट भर सकते हैं और अकेले पाइप A और पाइप B टैंक को क्रमशः x/4 मिनट और x/5 मिनट में भर सकते हैं। अकेला पाइप C टैंक को 10 मिनट में खाली कर सकता है। अकेले पाइप A द्वारा टैंक को भरने में लिया गया समय ज्ञात कीजिए।

A. 10 minutes
B. 18 minutes
C. 20 minutes
D. 16 minutes
E. None of these

Option “C” is correct.

1/A + 1/B – 1/C = 1/x

4/x + 5/x – 1/10 = 1/x

4/x + 5/x – 1/x = 1/10

8/x = 1/10

x = 80 minutes

Time taken by Pipe A alone to fill the tank = 80/4 = 20 minutes

70. Pipe P can fill 3/5th of a tank in x minutes and Pipe Q alone can fill the full tank in 2.5x minutes and both pipes together can fill the tank in 24 minutes. Find the time taken by Pipe P alone to fill a tank?

पाइप P एक टैंक का 3/5 भाग x मिनट में भर सकता है और अकेला पाइप Q पूर्ण टैंक को 2.5x मिनट में भर सकता है और एकसाथ दोनों पाइप टैंक को 24 मिनट में भर सकते हैं। अकेले पाइप P द्वारा एक टैंक को भरने में लिया गया समय ज्ञात कीजिये?

A. 40 minutes
B. 60 minutes
C. 50 minutes
D. 48 minutes
E. None of these

Option “A” is correct.

Time taken Pipe P alone to fill the full tank = x * 5/3 = 5x/3 minutes

3/5x + 1/2.5x = 1/24

3/5x + 2/5x = 1/24

5/5x = 1/24

x = 24 minutes

Time taken Pipe P alone to fill the full tank = 5 * 24/3 = 40 minutes