Aptitude - Pipes and Cistern - Discussion
Discussion Forum : Pipes and Cistern - General Questions (Q.No. 10)
10.
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?
Answer: Option
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.
Discussion:
37 comments Page 1 of 4.
Kalpna said:
1 decade ago
Another method could be : 4/15+x/20=1
x=44/3 i.e 14 min 40 sec.
4/15 is the part filled by A in 4 mins
and x is the total time taken to fill the tank by B.
x=44/3 i.e 14 min 40 sec.
4/15 is the part filled by A in 4 mins
and x is the total time taken to fill the tank by B.
(1)
Priya P. said:
1 decade ago
@ kalpna.
Thanks. Really less time consuming.
Thanks. Really less time consuming.
(1)
Santhu said:
1 decade ago
Hi kalpana how u solve this x value
4/15+x/20=1
from above equation x val is = 46/3 its not 44/3....
4/15+x/20=1
from above equation x val is = 46/3 its not 44/3....
Naveen said:
1 decade ago
Hi santhu.
Its 44/3 only.
Its 44/3 only.
Satyajit said:
1 decade ago
@thnx kalpna
Talha said:
1 decade ago
How is 44/3 = 14 min 40 sec ?
Anjali said:
1 decade ago
Hi Kalpna,
How you write 44/3 = 14 min 40 sec ?
How you write 44/3 = 14 min 40 sec ?
Sundar said:
1 decade ago
@Talha
It is simple yaar.
44/3 minutes =
= 14(2/3) mins
= 14 min 40 seconds ( 2/3 x 60 = 40 seconds)
= 14 min 40 seconds.
It is simple yaar.
44/3 minutes =
= 14(2/3) mins
= 14 min 40 seconds ( 2/3 x 60 = 40 seconds)
= 14 min 40 seconds.
Preeti said:
1 decade ago
Another method could be : (1/15 + 1/20)*4 + (1/20)*x-4 = 1
7/15 + (X-4)/20 = 1
Hence x=44/3.
= 14(2/3) mins
= 14 min 40 seconds ( 2/3 x 60 = 40 seconds)
Here 7/15 is the part filled by (A + B) in 4 mins.
and (x-4) is the total time taken to fill the tank by B alone.
Here 1 means show full tank.
7/15 + (X-4)/20 = 1
Hence x=44/3.
= 14(2/3) mins
= 14 min 40 seconds ( 2/3 x 60 = 40 seconds)
Here 7/15 is the part filled by (A + B) in 4 mins.
and (x-4) is the total time taken to fill the tank by B alone.
Here 1 means show full tank.
Mahi said:
1 decade ago
Thanks kalapana your solution is time consuming.
Post your comments here:
Quick links
Quantitative Aptitude
Verbal (English)
Reasoning
Programming
Interview
Placement Papers