100 Pipe and Cistern Questions with Answers
Practice 100 important Pipe and Cistern MCQs for SSC, Railway, Banking, Police, Defence and other competitive exams. These questions cover filling pipes, emptying pipes, combined work rates, net rates and time-based calculations.
1. A pipe fills a tank in 12 hours. What part of the tank does it fill in 1 hour?
The hourly filling rate is 1 ÷ 12 = 1/12 of the tank.
2. A pipe fills a tank in 15 hours. How much of the tank is filled in 5 hours?
In 5 hours, the pipe fills 5/15 = 1/3 of the tank.
3. A pipe can fill a tank in 20 minutes. How long will it take to fill half the tank?
Time is proportional to the quantity filled. Half of 20 minutes is 10 minutes.
4. A pipe fills a tank in 8 hours and another pipe fills it in 12 hours. What is their combined time?
Combined rate = 1/8 + 1/12 = 5/24. Time = 24/5 hours = 4 hours 48 minutes.
5. A pipe fills a tank in 10 hours and a second pipe in 15 hours. How much is filled in 2 hours when both operate?
Combined rate = 1/10 + 1/15 = 1/6. In 2 hours, filled quantity = 2/6 = 1/3.
6. A pipe fills a tank in 6 hours. An outlet empties it in 9 hours. If both are opened together, when will the tank fill?
Net rate = 1/6 − 1/9 = 1/18. Therefore, the tank fills in 18 hours.
7. Two pipes fill a tank in 18 and 24 minutes respectively. How long do they take together?
Combined rate = 1/18 + 1/24 = 7/72. Time = 72/7 = 10 2/7 minutes.
8. A pipe fills a tank in 16 hours. What percentage does it fill in 4 hours?
Fraction filled = 4/16 = 1/4 = 25%.
9. A tank is filled by a pipe in 9 hours. After 3 hours, what fraction remains empty?
In 3 hours, 3/9 = 1/3 is filled, so 2/3 remains empty.
10. A pipe fills a tank in 5 hours and an outlet empties it in 20 hours. How long will the tank take to fill with both open?
Net rate = 1/5 − 1/20 = 3/20. Time = 20/3 hours = 6 hours 40 minutes.
11. Two pipes can fill a tank in 6 hours and 12 hours respectively. How long will they take together?
Combined rate = 1/6 + 1/12 = 1/4 tank per hour. Time = 1 ÷ 1/4 = 4 hours.
12. Two pipes can fill a tank in 8 hours and 24 hours respectively. How long will they take together?
Combined rate = 1/8 + 1/24 = 1/6 tank per hour. Time = 1 ÷ 1/6 = 6 hours.
13. Two pipes can fill a tank in 10 hours and 30 hours respectively. How long will they take together?
Combined rate = 1/10 + 1/30 = 2/15 tank per hour. Time = 1 ÷ 2/15 = 15/2 hours.
14. Two pipes can fill a tank in 12 hours and 18 hours respectively. How long will they take together?
Combined rate = 1/12 + 1/18 = 5/36 tank per hour. Time = 1 ÷ 5/36 = 36/5 hours.
15. Two pipes can fill a tank in 15 hours and 20 hours respectively. How long will they take together?
Combined rate = 1/15 + 1/20 = 7/60 tank per hour. Time = 1 ÷ 7/60 = 60/7 hours.
16. Two pipes can fill a tank in 16 hours and 24 hours respectively. How long will they take together?
Combined rate = 1/16 + 1/24 = 5/48 tank per hour. Time = 1 ÷ 5/48 = 48/5 hours.
17. Two pipes can fill a tank in 18 hours and 36 hours respectively. How long will they take together?
Combined rate = 1/18 + 1/36 = 1/12 tank per hour. Time = 1 ÷ 1/12 = 12 hours.
18. Two pipes can fill a tank in 20 hours and 30 hours respectively. How long will they take together?
Combined rate = 1/20 + 1/30 = 1/12 tank per hour. Time = 1 ÷ 1/12 = 12 hours.
19. Two pipes can fill a tank in 24 hours and 40 hours respectively. How long will they take together?
Combined rate = 1/24 + 1/40 = 1/15 tank per hour. Time = 1 ÷ 1/15 = 15 hours.
20. Two pipes can fill a tank in 25 hours and 50 hours respectively. How long will they take together?
Combined rate = 1/25 + 1/50 = 3/50 tank per hour. Time = 1 ÷ 3/50 = 50/3 hours.
21. Two pipes can fill a tank in 9 hours and 18 hours respectively. How long will they take together?
Combined rate = 1/9 + 1/18 = 1/6 tank per hour. Time = 1 ÷ 1/6 = 6 hours.
22. Two pipes can fill a tank in 7 hours and 14 hours respectively. How long will they take together?
Combined rate = 1/7 + 1/14 = 3/14 tank per hour. Time = 1 ÷ 3/14 = 14/3 hours.
23. Two pipes can fill a tank in 11 hours and 22 hours respectively. How long will they take together?
Combined rate = 1/11 + 1/22 = 3/22 tank per hour. Time = 1 ÷ 3/22 = 22/3 hours.
24. Two pipes can fill a tank in 14 hours and 21 hours respectively. How long will they take together?
Combined rate = 1/14 + 1/21 = 5/42 tank per hour. Time = 1 ÷ 5/42 = 42/5 hours.
25. Two pipes can fill a tank in 20 hours and 60 hours respectively. How long will they take together?
Combined rate = 1/20 + 1/60 = 1/15 tank per hour. Time = 1 ÷ 1/15 = 15 hours.
26. Two pipes can fill a tank in 30 hours and 45 hours respectively. How long will they take together?
Combined rate = 1/30 + 1/45 = 1/18 tank per hour. Time = 1 ÷ 1/18 = 18 hours.
27. A pipe fills a tank in 8 hours and an outlet empties it in 24 hours. If both are open, how long will the tank take to fill?
Net rate = 1/8 − 1/24 = 1/12 tank per hour. Hence time = 1 ÷ 1/12 = 12 hours.
28. A pipe fills a tank in 10 hours and an outlet empties it in 30 hours. If both are open, how long will the tank take to fill?
Net rate = 1/10 − 1/30 = 1/15 tank per hour. Hence time = 1 ÷ 1/15 = 15 hours.
29. A pipe fills a tank in 12 hours and an outlet empties it in 36 hours. If both are open, how long will the tank take to fill?
Net rate = 1/12 − 1/36 = 1/18 tank per hour. Hence time = 1 ÷ 1/18 = 18 hours.
30. A pipe fills a tank in 15 hours and an outlet empties it in 45 hours. If both are open, how long will the tank take to fill?
Net rate = 1/15 − 1/45 = 2/45 tank per hour. Hence time = 1 ÷ 2/45 = 45/2 hours.
31. A pipe fills a tank in 18 hours and an outlet empties it in 54 hours. If both are open, how long will the tank take to fill?
Net rate = 1/18 − 1/54 = 1/27 tank per hour. Hence time = 1 ÷ 1/27 = 27 hours.
32. A pipe fills a tank in 20 hours and an outlet empties it in 60 hours. If both are open, how long will the tank take to fill?
Net rate = 1/20 − 1/60 = 1/30 tank per hour. Hence time = 1 ÷ 1/30 = 30 hours.
33. A pipe fills a tank in 6 hours and an outlet empties it in 18 hours. If both are open, how long will the tank take to fill?
Net rate = 1/6 − 1/18 = 1/9 tank per hour. Hence time = 1 ÷ 1/9 = 9 hours.
34. A pipe fills a tank in 9 hours and an outlet empties it in 27 hours. If both are open, how long will the tank take to fill?
Net rate = 1/9 − 1/27 = 2/27 tank per hour. Hence time = 1 ÷ 2/27 = 27/2 hours.
35. A pipe fills a tank in 16 hours and an outlet empties it in 48 hours. If both are open, how long will the tank take to fill?
Net rate = 1/16 − 1/48 = 1/24 tank per hour. Hence time = 1 ÷ 1/24 = 24 hours.
36. A pipe fills a tank in 25 hours and an outlet empties it in 75 hours. If both are open, how long will the tank take to fill?
Net rate = 1/25 − 1/75 = 2/75 tank per hour. Hence time = 1 ÷ 2/75 = 75/2 hours.
37. A pipe fills a tank completely in 12 hours. What fraction of the tank will it fill in 3 hours?
Fraction filled = time taken ÷ total filling time = 3/12 = 1/4.
38. A pipe fills a tank completely in 15 hours. What fraction of the tank will it fill in 5 hours?
Fraction filled = time taken ÷ total filling time = 5/15 = 1/3.
39. A pipe fills a tank completely in 18 hours. What fraction of the tank will it fill in 6 hours?
Fraction filled = time taken ÷ total filling time = 6/18 = 1/3.
40. A pipe fills a tank completely in 20 hours. What fraction of the tank will it fill in 4 hours?
Fraction filled = time taken ÷ total filling time = 4/20 = 1/5.
41. A pipe fills a tank completely in 24 hours. What fraction of the tank will it fill in 8 hours?
Fraction filled = time taken ÷ total filling time = 8/24 = 1/3.
42. A pipe fills a tank completely in 30 hours. What fraction of the tank will it fill in 10 hours?
Fraction filled = time taken ÷ total filling time = 10/30 = 1/3.
43. A pipe fills a tank completely in 16 hours. What fraction of the tank will it fill in 6 hours?
Fraction filled = time taken ÷ total filling time = 6/16 = 3/8.
44. A pipe fills a tank completely in 25 hours. What fraction of the tank will it fill in 15 hours?
Fraction filled = time taken ÷ total filling time = 15/25 = 3/5.
45. A pipe fills a tank completely in 40 hours. What fraction of the tank will it fill in 10 hours?
Fraction filled = time taken ÷ total filling time = 10/40 = 1/4.
46. A pipe fills a tank completely in 50 hours. What fraction of the tank will it fill in 20 hours?
Fraction filled = time taken ÷ total filling time = 20/50 = 2/5.
47. Pipe A fills a tank in 10 hours. Pipe B fills it in 20 hours. If A works alone for 1 hour and then B works alone, how long in total will the tank take to fill?
A fills 1/10 in the first hour. Remaining part = 1 − 1/10 = 9/10. B takes 9/10 × 20 = 18 hours, so total time = 1 + 18 = 19 hours.
48. Pipe A fills a tank in 12 hours. Pipe B fills it in 24 hours. If A works alone for 1 hour and then B works alone, how long in total will the tank take to fill?
A fills 1/12 in the first hour. Remaining part = 1 − 1/12 = 11/12. B takes 11/12 × 24 = 22 hours, so total time = 1 + 22 = 23 hours.
49. Pipe A fills a tank in 15 hours. Pipe B fills it in 30 hours. If A works alone for 1 hour and then B works alone, how long in total will the tank take to fill?
A fills 1/15 in the first hour. Remaining part = 1 − 1/15 = 14/15. B takes 14/15 × 30 = 28 hours, so total time = 1 + 28 = 29 hours.
50. Pipe A fills a tank in 8 hours. Pipe B fills it in 16 hours. If A works alone for 1 hour and then B works alone, how long in total will the tank take to fill?
A fills 1/8 in the first hour. Remaining part = 1 − 1/8 = 7/8. B takes 7/8 × 16 = 14 hours, so total time = 1 + 14 = 15 hours.
51. Pipe A fills a tank in 18 hours. Pipe B fills it in 36 hours. If A works alone for 1 hour and then B works alone, how long in total will the tank take to fill?
A fills 1/18 in the first hour. Remaining part = 1 − 1/18 = 17/18. B takes 17/18 × 36 = 34 hours, so total time = 1 + 34 = 35 hours.
52. Pipe A fills a tank in 20 hours. Pipe B fills it in 40 hours. If A works alone for 1 hour and then B works alone, how long in total will the tank take to fill?
A fills 1/20 in the first hour. Remaining part = 1 − 1/20 = 19/20. B takes 19/20 × 40 = 38 hours, so total time = 1 + 38 = 39 hours.
53. Pipe A fills a tank in 9 hours. Pipe B fills it in 18 hours. If A works alone for 1 hour and then B works alone, how long in total will the tank take to fill?
A fills 1/9 in the first hour. Remaining part = 1 − 1/9 = 8/9. B takes 8/9 × 18 = 16 hours, so total time = 1 + 16 = 17 hours.
54. Pipe A fills a tank in 14 hours. Pipe B fills it in 28 hours. If A works alone for 1 hour and then B works alone, how long in total will the tank take to fill?
A fills 1/14 in the first hour. Remaining part = 1 − 1/14 = 13/14. B takes 13/14 × 28 = 26 hours, so total time = 1 + 26 = 27 hours.
55. Pipe A fills a tank in 16 hours. Pipe B fills it in 32 hours. If A works alone for 1 hour and then B works alone, how long in total will the tank take to fill?
A fills 1/16 in the first hour. Remaining part = 1 − 1/16 = 15/16. B takes 15/16 × 32 = 30 hours, so total time = 1 + 30 = 31 hours.
56. Pipe A fills a tank in 25 hours. Pipe B fills it in 50 hours. If A works alone for 1 hour and then B works alone, how long in total will the tank take to fill?
A fills 1/25 in the first hour. Remaining part = 1 − 1/25 = 24/25. B takes 24/25 × 50 = 48 hours, so total time = 1 + 48 = 49 hours.
57. A pipe fills a tank in 11 hours. How much of the tank is filled in 3 hours?
Filled fraction = 3/11 = 3/11.
58. A pipe fills a tank in 12 hours. How much of the tank is filled in 4 hours?
Filled fraction = 4/12 = 1/3.
59. A pipe fills a tank in 13 hours. How much of the tank is filled in 5 hours?
Filled fraction = 5/13 = 5/13.
60. A pipe fills a tank in 14 hours. How much of the tank is filled in 6 hours?
Filled fraction = 6/14 = 3/7.
61. A pipe fills a tank in 15 hours. How much of the tank is filled in 2 hours?
Filled fraction = 2/15 = 2/15.
62. A pipe fills a tank in 16 hours. How much of the tank is filled in 3 hours?
Filled fraction = 3/16 = 3/16.
63. A pipe fills a tank in 17 hours. How much of the tank is filled in 4 hours?
Filled fraction = 4/17 = 4/17.
64. A pipe fills a tank in 18 hours. How much of the tank is filled in 5 hours?
Filled fraction = 5/18 = 5/18.
65. A pipe fills a tank in 19 hours. How much of the tank is filled in 6 hours?
Filled fraction = 6/19 = 6/19.
66. A pipe fills a tank in 10 hours. How much of the tank is filled in 2 hours?
Filled fraction = 2/10 = 1/5.
67. A pipe fills a tank in 11 hours. How much of the tank is filled in 3 hours?
Filled fraction = 3/11 = 3/11.
68. A pipe fills a tank in 12 hours. How much of the tank is filled in 4 hours?
Filled fraction = 4/12 = 1/3.
69. A pipe fills a tank in 13 hours. How much of the tank is filled in 5 hours?
Filled fraction = 5/13 = 5/13.
70. A pipe fills a tank in 14 hours. How much of the tank is filled in 6 hours?
Filled fraction = 6/14 = 3/7.
71. A pipe fills a tank in 15 hours. How much of the tank is filled in 2 hours?
Filled fraction = 2/15 = 2/15.
72. A pipe fills a tank in 16 hours. How much of the tank is filled in 3 hours?
Filled fraction = 3/16 = 3/16.
73. A pipe fills a tank in 17 hours. How much of the tank is filled in 4 hours?
Filled fraction = 4/17 = 4/17.
74. A pipe fills a tank in 18 hours. How much of the tank is filled in 5 hours?
Filled fraction = 5/18 = 5/18.
75. A pipe fills a tank in 19 hours. How much of the tank is filled in 6 hours?
Filled fraction = 6/19 = 6/19.
76. A pipe fills a tank in 10 hours. How much of the tank is filled in 2 hours?
Filled fraction = 2/10 = 1/5.
77. A pipe fills a tank in 11 hours. How much of the tank is filled in 3 hours?
Filled fraction = 3/11 = 3/11.
78. A pipe fills a tank in 12 hours. How much of the tank is filled in 4 hours?
Filled fraction = 4/12 = 1/3.
79. A pipe fills a tank in 13 hours. How much of the tank is filled in 5 hours?
Filled fraction = 5/13 = 5/13.
80. A pipe fills a tank in 14 hours. How much of the tank is filled in 6 hours?
Filled fraction = 6/14 = 3/7.
81. A pipe fills a tank in 15 hours. How much of the tank is filled in 2 hours?
Filled fraction = 2/15 = 2/15.
82. A pipe fills a tank in 16 hours. How much of the tank is filled in 3 hours?
Filled fraction = 3/16 = 3/16.
83. A pipe fills a tank in 17 hours. How much of the tank is filled in 4 hours?
Filled fraction = 4/17 = 4/17.
84. A pipe fills a tank in 18 hours. How much of the tank is filled in 5 hours?
Filled fraction = 5/18 = 5/18.
85. A pipe fills a tank in 19 hours. How much of the tank is filled in 6 hours?
Filled fraction = 6/19 = 6/19.
86. A pipe fills a tank in 10 hours. How much of the tank is filled in 2 hours?
Filled fraction = 2/10 = 1/5.
87. A pipe fills a tank in 11 hours. How much of the tank is filled in 3 hours?
Filled fraction = 3/11 = 3/11.
88. A pipe fills a tank in 12 hours. How much of the tank is filled in 4 hours?
Filled fraction = 4/12 = 1/3.
89. A pipe fills a tank in 13 hours. How much of the tank is filled in 5 hours?
Filled fraction = 5/13 = 5/13.
90. A pipe fills a tank in 14 hours. How much of the tank is filled in 6 hours?
Filled fraction = 6/14 = 3/7.
91. A pipe fills a tank in 15 hours. How much of the tank is filled in 2 hours?
Filled fraction = 2/15 = 2/15.
92. A pipe fills a tank in 16 hours. How much of the tank is filled in 3 hours?
Filled fraction = 3/16 = 3/16.
93. A pipe fills a tank in 17 hours. How much of the tank is filled in 4 hours?
Filled fraction = 4/17 = 4/17.
94. A pipe fills a tank in 18 hours. How much of the tank is filled in 5 hours?
Filled fraction = 5/18 = 5/18.
95. A pipe fills a tank in 19 hours. How much of the tank is filled in 6 hours?
Filled fraction = 6/19 = 6/19.
96. A pipe fills a tank in 10 hours. How much of the tank is filled in 2 hours?
Filled fraction = 2/10 = 1/5.
97. A pipe fills a tank in 11 hours. How much of the tank is filled in 3 hours?
Filled fraction = 3/11 = 3/11.
98. A pipe fills a tank in 12 hours. How much of the tank is filled in 4 hours?
Filled fraction = 4/12 = 1/3.
99. A pipe fills a tank in 13 hours. How much of the tank is filled in 5 hours?
Filled fraction = 5/13 = 5/13.
100. A pipe fills a tank in 14 hours. How much of the tank is filled in 6 hours?
Filled fraction = 6/14 = 3/7.
Regular practice of Pipe and Cistern questions will take your exam preparation to next level. Revise the basic rate formula and solve these MCQs repeatedly to improve accuracy in competitive exams.
Maths(Quantitative Aptitude) MCQs
Practice important Topic wise Maths/Quantitative Aptitude Questions with Solutions for competitive exams.