Aptitude - Pipes and Cistern - Discussion
Discussion Forum : Pipes and Cistern - General Questions (Q.No. 3)
3.
A pump can fill a tank with water in 2 hours. Because of a leak, it took 2
hours to fill the tank. The leak can drain all the water of the tank in:
hours to fill the tank. The leak can drain all the water of the tank in:Answer: Option
Explanation:
| Work done by the leak in 1 hour = |  |
1 | - | 3 |  |
= | 1 | . |
| 2 | 7 | 14 |
Leak will empty the tank in 14 hrs.
Discussion:
90 comments Page 5 of 9.
Mrunal said:
8 years ago
Here is a different solution.
Let tank capacity is 42 liters.
Pump A filling rate is = 42 liters/ 2 hours= 21 lph.
Pump A filling rate due to the leak is = 42 liters/ 7/3 hours = 18 lph.
Now the leaking rate is 21-18= 3 lph.
Leak can empty tank in = 42 liters/ 3 lph= 14 hrs.
Hope this is simple and easy to understand.
Let tank capacity is 42 liters.
Pump A filling rate is = 42 liters/ 2 hours= 21 lph.
Pump A filling rate due to the leak is = 42 liters/ 7/3 hours = 18 lph.
Now the leaking rate is 21-18= 3 lph.
Leak can empty tank in = 42 liters/ 3 lph= 14 hrs.
Hope this is simple and easy to understand.
Swati said:
8 years ago
Why 42/3? @Anuj.
Pranav said:
8 years ago
Ans : D
Tank fill without leak = 2 hours
Tank fill with leak = 2 1/3 hours
= 2/1 * 1/3
= 7/3 hours
(imp)
The time taken to drain a tank is
= Part filled in 1 hour (without leak) - partly filled in 1 hour (with leak).
= 1/2 - 1/ 7/3
=> 1/ 7/3 = 3/7
= 1/2 - 3/7
= 1/14.
So, time taken to drain the tank is 14 hours.
Tank fill without leak = 2 hours
Tank fill with leak = 2 1/3 hours
= 2/1 * 1/3
= 7/3 hours
(imp)
The time taken to drain a tank is
= Part filled in 1 hour (without leak) - partly filled in 1 hour (with leak).
= 1/2 - 1/ 7/3
=> 1/ 7/3 = 3/7
= 1/2 - 3/7
= 1/14.
So, time taken to drain the tank is 14 hours.
Anuj said:
8 years ago
Without leakage a takes 2 hours with,
leakage 7/3 hour take lcm of 7/3 *3=7and 2*3=6.
lcm of 6 and 7=42 it takes more 1/3 hour so divide 42 by 3 =42/3 =14.
leakage 7/3 hour take lcm of 7/3 *3=7and 2*3=6.
lcm of 6 and 7=42 it takes more 1/3 hour so divide 42 by 3 =42/3 =14.
Sandhya said:
8 years ago
How 1/3 got over there? please explain.
SAHID said:
8 years ago
First, it takes 120 min for leakage it lake (120+1/3*60=120+20)=140 min then LCM(120 and 140 it. It give 840min. 840/60 = 14hours.
Ankit said:
8 years ago
Good explanation. Thank you @Deepi.
Anjali tengli said:
8 years ago
Without leakage it takes 2 hrs.
In 1 hr it take 1/2.
With leakage, it takes 7/3
In 1 hr 1/7/3 I.e. 3/7.
1/2 - 3/7= 11/14.
In 1 hr it take 1/2.
With leakage, it takes 7/3
In 1 hr 1/7/3 I.e. 3/7.
1/2 - 3/7= 11/14.
Murali said:
8 years ago
A pipe can fill a tank in 3 hours. Because of the leak in the bottom, it is filled in 4 hours. If the tank is full, how much time will the leak take to empty it?
Can anyone solve it?
Can anyone solve it?
Champion said:
8 years ago
How can we say that 1/14 part of tank fills in 1 hour and it takes 14 hrs to drain all water?
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