Aptitude - Pipes and Cistern - Discussion
Discussion Forum : Pipes and Cistern - General Questions (Q.No. 11)
11.
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:
Answer: Option
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.
Discussion:
67 comments Page 6 of 7.
Jayaprakash said:
8 years ago
Great @Indrajit.
Khagendra said:
8 years ago
Most effective solution, Thanks @Laxman.
Pranathi said:
8 years ago
Thank you @Reshma.
Akshatha N said:
8 years ago
Why cannot we take faster pipe=3x, instead of x/3?
Akhil galla said:
7 years ago
Why can't we take 3x for faster one instead of x/3 for faster one?
(1)
Dhilber said:
7 years ago
Let take x is the time taken by a faster pipe and 3x be the time taken by the slowest pipe.
hence 3x+x=36,
x=9.
which means in total 36 min.
9 min taken by fastest pipe and remaining 27 min taken by the slowest pipe.
So instead of using the fastest pipe, we use the slowest pipe then it takes 3 times more time than the slowest pipe.
Hence, 9*3=27.
So total time taken will be 27+27=54.
Please correct me, if I am wrong.
hence 3x+x=36,
x=9.
which means in total 36 min.
9 min taken by fastest pipe and remaining 27 min taken by the slowest pipe.
So instead of using the fastest pipe, we use the slowest pipe then it takes 3 times more time than the slowest pipe.
Hence, 9*3=27.
So total time taken will be 27+27=54.
Please correct me, if I am wrong.
(2)
Rishabh said:
7 years ago
So as per ques.(simple trick).
Pipe A (slower)complete its work to 1unit/min.
Then Pipe B (faster)complete its work to 3unit/min.
Then total unit in 1 min=4units/min.
Then total units in total time=4*36=144units.
NOW B(Slower pipe) time=(1min/1unit)x144units = 144units.
Pipe A (slower)complete its work to 1unit/min.
Then Pipe B (faster)complete its work to 3unit/min.
Then total unit in 1 min=4units/min.
Then total units in total time=4*36=144units.
NOW B(Slower pipe) time=(1min/1unit)x144units = 144units.
(9)
Santosh said:
7 years ago
Thanks for explaining @Mahima.
CHANDRA MOHAN NAGAR said:
5 years ago
Work inversely proportional to time.
Fast pipe time = x.
Slow pipe time = 3x (according to question).
Together time = 36min.
1/36 = 1/x + 1/3x.
36*4 = 3x.
3x time take by slow pipe = 144 Answer.
Fast pipe time = x.
Slow pipe time = 3x (according to question).
Together time = 36min.
1/36 = 1/x + 1/3x.
36*4 = 3x.
3x time take by slow pipe = 144 Answer.
(1)
Bangari chowdary said:
5 years ago
Thanks all for explaining.
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