Aptitude - Pipes and Cistern - Discussion
Discussion Forum : Pipes and Cistern - General Questions (Q.No. 13)
13.
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?
Answer: Option
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 |
![]() |
![]() |
1 | x 1 x | 3 | ![]() |
= | 3 | hours i.e., 45 mins. |
2 | 2 | 4 |
So, total time taken = 3 hrs. 45 mins.
Discussion:
53 comments Page 1 of 6.
Sapna Singh Lodhi said:
6 months ago
The half tank filled in 3 hours since the full took 6 hours.
So, the rest half will be filled by 4 tap = 3 * 60/4 = 45.
Complete time to fill the tank = 3 hours 45 min.
So, the rest half will be filled by 4 tap = 3 * 60/4 = 45.
Complete time to fill the tank = 3 hours 45 min.
(1)
Hemanth said:
2 years ago
We know Rate * Time = Capacity.
Rate = 1/6 ,
Capacity = 1/2.
1/6 * time =1/2
Here time = 3hrs for capacity half.
Next, more three pipes total of 4 pipes.
4 * 1/6 = 2/3.
Rate for 4 pipes is 2/3, Time=?, Capacity = another 1/2,
2/3 * time = 1/2.
Here time = 3/4 = 0.75hrs(0.75*60min).
Total time = 3hrs + 0.75hrs(45 min).
Rate = 1/6 ,
Capacity = 1/2.
1/6 * time =1/2
Here time = 3hrs for capacity half.
Next, more three pipes total of 4 pipes.
4 * 1/6 = 2/3.
Rate for 4 pipes is 2/3, Time=?, Capacity = another 1/2,
2/3 * time = 1/2.
Here time = 3/4 = 0.75hrs(0.75*60min).
Total time = 3hrs + 0.75hrs(45 min).
(8)
Tushar Pawar said:
3 years ago
They asked total time, so half tank is filled in 3 hour and later it takes 45 min as we calculated. Therefore 3 hour and 45 min.
(3)
Evans Twineamatsiko said:
3 years ago
Good explanation, Thanks. @Vicky!
(1)
Teja said:
4 years ago
Time taken by 1tap to fill the tank is 6hrs, then half is 3hrs (work done by 1 tap).
So,
3 * (1/6) + x * (4/6) = 1,
x = 3/4.
So,
3 * (1/6) + x * (4/6) = 1,
x = 3/4.
(4)
GAGAn said:
5 years ago
It is assumed that all the taps are equally efficient, so we have divided 3 hrs, i.e 180 min into 4 equal part, that how 45 min came.
(10)
Gopi said:
5 years ago
@ Sravanthi :
only one tap fill the half tank. So, the remaining four should fill the remaining half tank.
Hence. 1 - 1/2 = 1/2.
It's should not be 1-2/3.
only one tap fill the half tank. So, the remaining four should fill the remaining half tank.
Hence. 1 - 1/2 = 1/2.
It's should not be 1-2/3.
Sriramamurthi said:
5 years ago
Guys, it is very easy.
A tap can fill a tank by 6 hrs. Then one tap is closed after 6 hrs which means 6/2=3 hrs.
Then 3 more taps are opened so now totally there are 4 taps are opened.
We are having remaining time will be 6-3 =3 hrs.
So find 3/4 you get 0. 75 hrs which means 45 mins.
So the Answer will be 3hrs 45 mins.
Hope it will help you.
A tap can fill a tank by 6 hrs. Then one tap is closed after 6 hrs which means 6/2=3 hrs.
Then 3 more taps are opened so now totally there are 4 taps are opened.
We are having remaining time will be 6-3 =3 hrs.
So find 3/4 you get 0. 75 hrs which means 45 mins.
So the Answer will be 3hrs 45 mins.
Hope it will help you.
(12)
M Ganesh said:
5 years ago
Here we are assuming rate =100
As per the statement,
A
R=100 h=? Capacity =300
=300/100=3.
A+B+C+D =300/400=0.75=45min
=> 3hr +45 min = 3hr 45.
As per the statement,
A
R=100 h=? Capacity =300
=300/100=3.
A+B+C+D =300/400=0.75=45min
=> 3hr +45 min = 3hr 45.
Anomie said:
5 years ago
Tank filled in 1hr =6units.
For half an hour =3units.
Remaining 3units.
Now 3 more taps.....+previous 1 tap =4taps.
Efficiency =3/4.
Total =3*3/4(60)=3hr 45min.
For half an hour =3units.
Remaining 3units.
Now 3 more taps.....+previous 1 tap =4taps.
Efficiency =3/4.
Total =3*3/4(60)=3hr 45min.
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