A pipe connected with a tank or a cistern or a reservoir, that fills it, is known as an inlet.
Outlet:
A pipe connected with a tank or cistern or reservoir, emptying it, is known as an outlet.
If a pipe can fill a tank in x hours, then:
part filled in 1 hour =
1
.
x
If a pipe can empty a tank in y hours, then:
part emptied in 1 hour =
1
.
y
If a pipe can fill a tank in x hours and another pipe can empty the full tank in y hours (where y > x), then on opening both the pipes, then
the net part filled in 1 hour =
1
–
1
.
x
y
If a pipe can fill a tank in x hours and another pipe can empty the full tank in y hours (where x > y), then on opening both the pipes, then
the net part emptied in 1 hour =
1
–
1
.
y
x
Questions:
Level-I:
1.
Three pipes A, B and C can fill a tank from empty to full in 30 minutes, 20 minutes, and 10 minutes respectively. When the tank is empty, all the three pipes are opened. A, B and C discharge chemical solutions P,Q and R respectively. What is the proportion of the solution R in the liquid in the tank after 3 minutes?
Pipes A and B can fill a tank in 5 and 6 hours respectively. Pipe C can empty it in 12 hours. If all the three pipes are opened together, then the tank will be filled in:
Two pipes A and B can fill a cistern in 37 minutes and 45 minutes respectively. Both pipes are opened. The cistern will be filled in just half an hour, if the B is turned off after:
A tank is filled by three pipes with uniform flow. The first two pipes operating simultaneously fill the tank in the same time during which the tank is filled by the third pipe alone. The second pipe fills the tank 5 hours faster than the first pipe and 4 hours slower than the third pipe. The time required by the first pipe is:
Two pipes can fill a tank in 20 and 24 minutes respectively and a waste pipe can empty 3 gallons per minute. All the three pipes working together can fill the tank in 15 minutes. The capacity of the tank is:
A tank is filled in 5 hours by three pipes A, B and C. The pipe C is twice as fast as B and B is twice as fast as A. How much time will pipe A alone take to fill the tank?
Two pipes A and B together can fill a cistern in 4 hours. Had they been opened separately, then B would have taken 6 hours more than A to fill the cistern. How much time will be taken by A to fill the cistern separately?
Two pipes A and B can fill a tank in 15 minutes and 20 minutes respectively. Both the pipes are opened together but after 4 minutes, pipe A is turned off. What is the total time required to fill the tank?
One pipe can fill a tank three times as fast as another pipe. If together the two pipes can fill the tank in 36 minutes, then the slower pipe alone will be able to fill the tank in:
A large tanker can be filled by two pipes A and B in 60 minutes and 40 minutes respectively. How many minutes will it take to fill the tanker from empty state if B is used for half the time and A and B fill it together for the other half?
A tap can fill a tank in 6 hours. After half the tank is filled, three more similar taps are opened. What is the total time taken to fill the tank completely?
Three taps A, B and C can fill a tank in 12, 15 and 20 hours respectively. If A is open all the time and B and C are open for one hour each alternately, the tank will be full in:
Three pipes A, B and C can fill a tank in 6 hours. After working at it together for 2 hours, C is closed and A and B can fill the remaining part in 7 hours. The number of hours taken by C alone to fill the tank is:
Even with all the three statements, answer cannot be given.
Answers:
Level-I:
Answer:1 Option B
Explanation:
Part filled by (A + B + C) in 3 minutes = 3
1
+
1
+
1
=
3 x
11
=
11
.
30
20
10
60
20
Part filled by C in 3 minutes =
3
.
10
Required ratio =
3
x
20
=
6
.
10
11
11
Answer:2 Option C
Explanation:
Net part filled in 1 hour
1
+
1
–
1
=
17
.
5
6
12
60
The tank will be full in
60
hours i.e., 3
9
hours.
17
17
Answer:3 Option D
Explanation:
Work done by the leak in 1 hour =
1
–
3
=
1
.
2
7
14
Leak will empty the tank in 14 hrs.
Answer:4 Option B
Explanation:
Let B be turned off after x minutes. Then,
Part filled by (A + B) in x min. + Part filled by A in (30 –x) min. = 1.
x
2
+
1
+ (30 – x).
2
= 1
75
45
75
11x
+
(60 -2x)
= 1
225
75
11x + 180 – 6x = 225.
x = 9.
Answer:5 Option C
Explanation:
Suppose, first pipe alone takes x hours to fill the tank .
Then, second and third pipes will take (x -5) and (x – 9) hours respectively to fill the tank.
1
+
1
=
1
x
(x – 5)
(x – 9)
x – 5 + x
=
1
x(x – 5)
(x – 9)
(2x – 5)(x – 9) = x(x – 5)
x2 – 18x + 45 = 0
(x – 15)(x – 3) = 0
x = 15. [neglecting x = 3]
Answer:6 Option C
Explanation:
Work done by the waste pipe in 1 minute =
1
–
1
+
1
15
20
24
=
1
–
11
15
120
= –
1
. [-ve sign means emptying]
40
Volume of
1
part = 3 gallons.
40
Volume of whole = (3 x 40) gallons = 120 gallon
Answer:7 Option C
Explanation:
Suppose pipe A alone takes x hours to fill the tank.
Then, pipes B and C will take
x
and
x
hours respectively to fill the tank.
2
4
1
+
2
+
4
=
1
x
x
x
5
7
=
1
x
5
x = 35 hrs.
Answer:8 Option C
Explanation:
Let the cistern be filled by pipe A alone in x hours.
Then, pipe B will fill it in (x + 6) hours.
1
+
1
=
1
x
(x + 6)
4
x + 6 + x
=
1
x(x + 6)
4
x2 – 2x – 24 = 0
(x -6)(x + 4) = 0
x = 6. [neglecting the negative value of x]
Answer:9 Option A
Explanation:
Part filled by A in 1 min =
1
.
20
Part filled by B in 1 min =
1
.
30
Part filled by (A + B) in 1 min =
1
+
1
=
1
.
20
30
12
Both pipes can fill the tank in 12 minutes.
Answer:10 Option D
Explanation:
Part filled in 4 minutes = 4
1
+
1
=
7
.
15
20
15
Remaining part =
1 –
7
=
8
.
15
15
Part filled by B in 1 minute =
1
20
1
:
8
:: 1 : x
20
15
x =
8
x 1 x 20
= 10
2
min = 10 min. 40 sec.
15
3
The tank will be full in (4 min. + 10 min. + 40 sec.) = 14 min. 40 sec.
Level-II:
Answer:11 Option C
Explanation:
Let the slower pipe alone fill the tank in x minutes.
Then, faster pipe will fill it in
x
minutes.
3
1
+
3
=
1
x
x
36
4
=
1
x
36
x = 144 min.
Answer:12 Option D
Explanation:
Part filled by (A + B) in 1 minute =
1
+
1
=
1
.
60
40
24
Suppose the tank is filled in x minutes.
Then,
x
1
+
1
= 1
2
24
40
x
x
1
= 1
2
15
x = 30 min.
Answer:13 Option B
Explanation:
Time taken by one tap to fill half of the tank = 3 hrs.
Part filled by the four taps in 1 hour =
4 x
1
=
2
.
6
3
Remaining part =
1 –
1
=
1
.
2
2
2
:
1
:: 1 : x
3
2
x =
1
x 1 x
3
=
3
hours i.e., 45 mins.
2
2
4
So, total time taken = 3 hrs. 45 mins.
Answer:14 Option C
Explanation:
(A + B)’s 1 hour’s work =
1
+
1
=
9
=
3
.
12
15
60
20
(A + C)’s hour’s work =
1
+
1
=
8
=
2
.
12
20
60
15
Part filled in 2 hrs =
3
+
2
=
17
.
20
15
60
Part filled in 6 hrs =
3 x
17
=
17
.
60
20
Remaining part =
1 –
17
=
3
.
20
20
Now, it is the turn of A and B and
3
part is filled by A and B in 1 hour.
20
Total time taken to fill the tank = (6 + 1) hrs = 7 hrs.
Answer:15 Option C
Explanation:
Part filled in 2 hours =
2
=
1
6
3
Remaining part =
1 –
1
=
2
.
3
3
(A + B)’s 7 hour’s work =
2
3
(A + B)’s 1 hour’s work =
2
21
C’s 1 hour’s work = { (A + B + C)’s 1 hour’s work } – { (A + B)’s 1 hour’s work }
=
1
–
2
=
1
6
21
14
C alone can fill the tank in 14 hours.
Answer:16 Option E
Explanation:
I. Time taken to fill the cistern without leak = 9 hours.
Part of cistern filled without leak in 1 hour =
1
9
II. Time taken to fill the cistern in presence of leak = 10 hours.
Net filling in 1 hour =
1
10
Work done by leak in 1 hour =
1
–
1
=
1
9
10
90
Leak will empty the full cistern in 90 hours.
Clearly, both I and II are necessary to answer the question.
Correct answer is (E).
Answer:17 Option E
Explanation:
I. A’s 1 minute’s filling work =
1
16
II. B’s 1 minute’s filling work =
1
8
(A + B)’s 1 minute’s emptying work =
1
–
1
=
1
8
16
16
Tank will be emptied in 16 minutes.
Thus, both I and II are necessary to answer the question.
Correct answer is (E).
Answer:18 Option B
Explanation:
II. Part of the tank filled by A in 1 hour =
1
4
III. Part of the tank filled by B in 1 hour =
1
6
(A + B)’s 1 hour’s work =
1
+
1
=
5
4
6
12
A and B will fill the tank in
12
hrs = 2 hrs 24 min.
5
So, II and III are needed.
Correct answer is (B).
,
Cisterns and pipes are two essential components of any water system. Cisterns store water, while pipes transport it from one place to another. Both cisterns and pipes come in a variety of materials and styles, and there are many factors to consider when choosing the right type for your needs.
Cisterns
A cistern is a water storage tank. Cisterns can be made from a variety of materials, including concrete, fiberglass, plastic, and steel. They can be installed above ground or underground.
Above-ground cisterns are typically made from concrete or fiberglass. They are easy to install and maintain, but they can be more susceptible to damage from the Elements.
Underground cisterns are typically made from plastic or steel. They are more protected from the elements, but they can be more difficult to install and maintain.
Cisterns can be used for a variety of purposes, including storing rainwater, greywater, and drinking water. Rainwater cisterns collect rainwater from roofs or other surfaces. Greywater cisterns collect wastewater from sinks, showers, and washing machines. Drinking water cisterns store water that has been treated to make it safe to drink.
Pipes
Pipes are used to transport water, sewage, and other fluids. They are made from a variety of materials, including PVC, HDPE, CPVC, cast iron, and ductile iron.
PVC pipes are lightweight and easy to install. They are also relatively inexpensive. However, they are not as durable as other types of pipes.
HDPE pipes are durable and resistant to corrosion. They are also relatively easy to install. However, they are more expensive than PVC pipes.
CPVC pipes are resistant to heat and chemicals. They are also relatively easy to install. However, they are more expensive than PVC and HDPE pipes.
Cast iron pipes are very durable and can withstand high pressure. However, they are heavy and difficult to install. They are also more expensive than other types of pipes.
Ductile iron pipes are a hybrid of cast iron and steel. They are durable, resistant to corrosion, and easy to install. However, they are more expensive than other types of pipes.
Pipe Fittings
Pipe fittings are used to connect pipes and to change the direction of the flow of water. They come in a variety of shapes and sizes, including elbows, tees, caps, reducers, and couplings.
Elbows are used to change the direction of the pipe. Tees are used to connect three pipes. Caps are used to seal the end of a pipe. Reducers are used to connect pipes of different sizes. Couplings are used to connect two pipes of the same size.
Pipe Installation
Pipes are installed in a trench that is dug in the ground. The trench should be deep enough to allow for the frost line in your area. The pipes should be laid on a bed of sand and then covered with dirt. The dirt should be compacted to prevent settling.
Pipe Maintenance
Pipes should be inspected regularly for leaks or damage. If a leak is found, it should be repaired immediately. Damaged pipes should be replaced.
Cistern Maintenance
Cisterns should be cleaned regularly to prevent the Growth of algae and bacteria. The cistern should be emptied and scrubbed with a mild detergent. The cistern should then be filled with fresh water.
Cisterns should also be inspected regularly for leaks or damage. If a leak is found, it should be repaired immediately. Damaged cisterns should be replaced.
Conclusion
Cisterns and pipes are essential components of any water system. They come in a variety of materials and styles, and there are many factors to consider when choosing the right type for your needs. It is important to install and maintain cisterns and pipes properly to ensure that they provide safe and reliable water for your home or business.
What is a pipe?
A pipe is a long, hollow tube that is used to carry fluids or gases. Pipes are made of a variety of materials, including Metal, plastic, and concrete. They are used in a wide range of applications, including plumbing, Irrigation, and transportation.
What is a cistern?
A cistern is a large container that is used to store water. Cisterns are typically made of concrete, stone, or brick. They are used in a variety of applications, including water storage for drinking, irrigation, and fire suppression.
What are the different types of pipes?
There are many different types of pipes, each with its own unique properties and applications. Some of the most common types of pipes include:
Metal pipes: Metal pipes are made of a variety of materials, including steel, copper, and aluminum. They are strong and durable, and they can withstand a variety of conditions. Metal pipes are often used in plumbing, irrigation, and transportation.
Plastic pipes: Plastic pipes are made of a variety of materials, including PVC, polyethylene, and polypropylene. They are lightweight and easy to install, and they are resistant to corrosion and chemicals. Plastic pipes are often used in plumbing, irrigation, and HVAC systems.
Concrete pipes: Concrete pipes are made of concrete, which is a strong and durable material. Concrete pipes are often used in sewer systems and storm drains.
Brick pipes: Brick pipes are made of brick, which is a strong and durable material. Brick pipes are often used in water supply systems and Drainage Systems.
What are the different types of cisterns?
There are many different types of cisterns, each with its own unique properties and applications. Some of the most common types of cisterns include:
Above-ground cisterns: Above-ground cisterns are located above the ground. They are typically made of concrete, steel, or plastic. Above-ground cisterns are often used in areas where there is limited space or where the ground is not suitable for digging a hole.
Underground cisterns: Underground cisterns are located below the ground. They are typically made of concrete, stone, or brick. Underground cisterns are often used in areas where there is plenty of space or where the ground is suitable for digging a hole.
Rainwater cisterns: Rainwater cisterns collect rainwater from roofs or other surfaces. They are typically made of concrete, steel, or plastic. Rainwater cisterns are often used to store water for drinking, irrigation, or other purposes.
Graywater cisterns: Graywater cisterns collect graywater, which is wastewater from sinks, showers, and washing machines. They are typically made of concrete, steel, or plastic. Graywater cisterns are often used to store water for irrigation or other purposes.
What are the benefits of using pipes?
There are many benefits to using pipes. Some of the benefits of using pipes include:
Pipes are efficient: Pipes are a very efficient way to transport fluids and gases. They can carry large volumes of material over long distances with very little loss of energy.
Pipes are versatile: Pipes can be used in a wide variety of applications. They are used in plumbing, irrigation, transportation, and many other industries.
Pipes are durable: Pipes are made of strong and durable materials. They can withstand a variety of conditions, including extreme temperatures, pressure, and chemicals.
Pipes are affordable: Pipes are a relatively affordable option for transporting fluids and gases. They are also easy to install and maintain.
What are the benefits of using cisterns?
There are many benefits to using cisterns. Some of the benefits of using cisterns include:
Cisterns can store water: Cisterns can store large amounts of water, which can be used for drinking, irrigation, or other purposes.
Cisterns can collect rainwater: Cisterns can collect rainwater, which can be used to reduce water bills and conserve water.
Cisterns can be used to store graywater: Cisterns can be used to store graywater, which can be used to irrigate Plants or flush toilets.
Cisterns can be used to reduce flooding: Cisterns can be used to store rainwater during storms, which can help to reduce flooding.
Cisterns can be used to improve water quality: Cisterns can be used to filter water, which can improve the quality of drinking water.
Sure, here are some MCQs without mentioning the topic Pipe and Cistern:
A pipe can fill a tank in 6 hours. Another pipe can fill the same tank in 8 hours. How long will it take both pipes to fill the tank together? (A) 4 hours (B) 5 hours (C) 6 hours (D) 7 hours
A pipe can empty a tank in 12 hours. Another pipe can empty the same tank in 18 hours. How long will it take both pipes to empty the tank together? (A) 6 hours (B) 9 hours (C) 12 hours (D) 18 hours
A pipe can fill a tank in 3 hours. Another pipe can fill the same tank in 4 hours. If both pipes are opened at the same time, how much of the tank will be filled in 1 hour? (A) 1/7 (B) 1/6 (C) 1/5 (D) 1/4
A pipe can empty a tank in 6 hours. Another pipe can empty the same tank in 8 hours. If both pipes are opened at the same time, how much of the tank will be emptied in 1 hour? (A) 1/14 (B) 1/12 (C) 1/10 (D) 1/8
A pipe can fill a tank in 6 hours. Another pipe can fill the same tank in 8 hours. If the first pipe is opened for 3 hours and then the second pipe is opened for 2 hours, how much of the tank will be filled? (A) 3/4 (B) 5/8 (C) 7/12 (D) 11/16
A pipe can empty a tank in 6 hours. Another pipe can empty the same tank in 8 hours. If the first pipe is opened for 3 hours and then the second pipe is opened for 2 hours, how much of the tank will be emptied? (A) 1/4 (B) 1/3 (C) 1/2 (D) 3/4
A pipe can fill a tank in 6 hours. Another pipe can fill the same tank in 8 hours. If the first pipe is opened for 1 hour and then the second pipe is opened for 2 hours, how much of the tank will be filled? (A) 1/6 (B) 1/4 (C) 1/3 (D) 1/2
A pipe can empty a tank in 6 hours. Another pipe can empty the same tank in 8 hours. If the first pipe is opened for 1 hour and then the second pipe is opened for 2 hours, how much of the tank will be emptied? (A) 1/12 (B) 1/8 (C) 1/6 (D) 1/4
A pipe can fill a tank in 6 hours. Another pipe can fill the same tank in 8 hours. If the first pipe is opened for 1 hour and then the second pipe is closed, how much of the tank will be filled? (A) 1/6 (B) 1/4 (C) 1/3 (D) 1/2
A pipe can empty a tank in 6 hours. Another pipe can empty the same tank in 8 hours. If the first pipe is opened for 1 hour and then the second pipe is closed, how much of the tank will be emptied? (A) 1/12 (B) 1/8 (C) 1/6 (D) 1/4
hours to fill the tank. The leak can drain all the water of the tank in:
minutes and 45 minutes respectively. Both pipes are opened. The cistern will be filled in just half an hour, if the B is turned off after:
Required ratio =
The tank will be full in
Leak will empty the tank in 14 hrs.
11x + 180 – 6x = 225.
x = 9.
(2x – 5)(x – 9) = x(x – 5)
x2 – 18x + 45 = 0
x = 15. [neglecting x = 3]
Volume of
x = 35 hrs.
x2 – 2x – 24 = 0
(x -6)(x + 4) = 0
x = 6. [neglecting the negative value of x]
Both pipes can fill the tank in 12 minutes. 
The tank will be full in (4 min. + 10 min. + 40 sec.) = 14 min. 40 sec.
x = 144 min.
x = 30 min.
Total time taken to fill the tank = (6 + 1) hrs = 7 hrs.
(A + B)’s 7 hour’s work =
C’s 1 hour’s work = { (A + B + C)’s 1 hour’s work } – { (A + B)’s 1 hour’s work }
C alone can fill the tank in 14 hours.
Leak will empty the full cistern in 90 hours.
Correct answer is (E).
Tank will be emptied in 16 minutes.
Correct answer is (E).
A and B will fill the tank in
Correct answer is (B).