Aakash Beniwal   8 years AGO

1/4 - 1/6 = 1/x
x is time taken to fill
ans is 12 hrs.

Like? Yes (2) | No   

Nafia Zuhana   8 years AGO

The efficiency 3 and 2 units. The difference between them 1 unitsper hr. So 12 units 12hrs.

Like? Yes (1) | No   

Meenakshi   8 years AGO

Net part filled in 1 hr = (1/4 - 1/6)
= 1/12
The tank will be filled in 12 hrs

Like? Yes (1) | No   

vikas rana   8 years AGO

tank filled in 1 hour = 1/4 -1/6=1/12
so net tank filled in 12 hours.

Like? Yes (1) | No   

mcamanjeet   8 years AGO

1/4-1/12 = (3-2)/12
=1/12
total hour = 12/1=12hour

Like? Yes (1) | No   

Vidhika K   8 years AGO

Time to fill an empty tank:
reciprocal of 1/4 - 1/6

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ABHINAV PUSHPAM   8 years AGO

Pipe A can fill a tank in 4 hours and pipe B can empty a tank in 6 hours.

If both the pipes are open together, Then 1 hours of work of both the pipes = 1/4 -1/6 = 1/12

So, the number of hours taken by them to fill it, is 12 hours.

Option 6)

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ANUJ KUMAR   8 years AGO

Pipe A 1hr work=1/4
Pipe B 1hr work=1/6
total in 1hr=(1/4)-(1/6)=1/12
so in 12 hrs the cistern can be fully filled by both these pipes working together

Like? Yes | No   

ashish   8 years AGO

Work done by tap "A" in 1 hr= 1/4
Work done by tap "B" in 1 hr= -1/6 (since it is making the tank empty.
so total work done = 1/4-1/6=1
Hence 12 hrs is the ans

Like? Yes (1) | No (1)  

raksha   8 years AGO

pipe hours taken one hour work
A 4 6
B -6 -4
-----
2
lcm of 4 and 6 is 24
so number of hours to fill is 24/2=12
ans =12

Like? Yes | No   

RAHUL KUMAR   8 years AGO

Pipe A can fill a tank in 4 hours and pipe B can empty a tank in 6 hours.

If both the pipes are open together, Then 1 hours of work of both the pipes = 1/4 -1/6 = 1/12

the number of hours taken by them to fill it, is 12 hours.

option (6)

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Lokesh Anand   8 years AGO

Tank filled in 1 hr = 1/4-1/6
= 1/12

Time taken to fill is 12 hrs

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Kumar Navendu   8 years AGO

volume of cistern = x
speed of pipe A=x/4
speed of pipe B=-x/6
net speed=x/4-x/6=x/12
time=volume/speed=x/(x/12)=12

Like? Yes | No   

Bharath daniel   8 years AGO

Total work=12units
Pipe A=3 units/hour
Pipe b= 2units/hour
Total work done =1units/hour
Time need to complete work =12hors

Like? Yes | No   

rahul Tiwari   8 years AGO

A one hour work is 1/4
B one hour work is 1/6 but it is in negative(removal of water) so total one hour work is
1/4-1/6=1/12
so 12 hours to take complete the work

Like? Yes (1) | No (1)  

Mukund Manohar   8 years AGO

In 1 hour,Pipe A can fill = 1/4 of the cistern
In 1 hour,Pipe B can empty = 1/6 of the cistern
In 1 hour,both pipes can fill = (1/4)-(1/6)
= (3-2)/12
= 1/12 of the cistern
So,12 hours will be taken to fill it.

Like? Yes | No   

Rajeet yadav   8 years AGO

1 hour work by A =1/4
1hour work by B= 1/6
net work=1/4-1/6
=1/12
hence 12 hour require

Like? Yes | No   

RAJNISH KUMAR   8 years AGO

(A+B) work in 1 hr together=1/4-1/6
=1/12
so, total 12 hrs required

Like? Yes | No   

Gokul Krishnan   8 years AGO

to fill a tank-->(x/4)
to empty a tank--->-(x/6)
Qn is on filling the tank,so=+1
hence(x/4)-(x/6)=1
By solving we get 12 Hours.

Like? Yes | No   

Arghyadeep Sarkar   8 years AGO

Pipe A can fill in 4 hrs => A can fill 1/4 cistern in 1 hr
Pipe B can empty in 6 hrs => B can empty 1/6 cistern in 1 hr
=> (1/4-1/6)=1/12 cistern can be filled in 1 hr if both pipes are opened => the cistern can be filled in 12 hrs if both pipes are opened

Like? Yes | No   

anirban maji   8 years AGO

filled by A in one hour = 1/4 unit and 1/6 unit left the tank through B in one hour and so tank filled in one hour = 1/4-1/6 = 1/12. so time taken to fill one unit is 12 hour.

Like? Yes | No   

suman    8 years AGO

let total amount of water is x;
first can fel x/4 part in one hour.
and second can remove x/6 part in one hour
let it take t time then (x/4-x/6)*t=x;
t=12

Like? Yes | No   

Kunal nemu   8 years AGO

The rate of filling of the 1st pipe = (1 tank filled)/(4 hours)
the rate of emptying of the 2nd pipe = - (1 tank empty)/(6 hours)
notice that the emptying rate has to have minus sign to make it opposite the filling rate
let 1/t = the rate of filling with both pipes
so 1/4 - 1/6 = 1/t
1/12 = 1/t
t=12
so the number of hours taken by them to fill it is 12hours

Like? Yes | No   

AVIJEET RAUSHAN   8 years AGO

1/4-1/6=1/12
this part will fill in one hour
therefore to fill the tank total require hours is 12

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Rohit Kumar   8 years AGO

A. B
4. 6
12
3. 2
A-B= 3-2= 1
so, 12�1= 12
hence 12 is answer option no. 6

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sanjeet kumar   8 years AGO

In 1 hour cistern is filled = 1/4 -1/6 = 1/12
So in 12 hours it will filled completely

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chelmeta   8 years AGO

assuming x liters as its capacity
per hour: x/4-x/6= x/12
so it requires 12 hrs
Option 6)

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Tanusree Misra   8 years AGO

In 1 hour a will fill 1/4th of tank and b will empty 1/6th of tank leaving 1/12th tank filled so it will take 12 hours to fill the tank

Like? Yes | No   

RAVAL   8 years AGO

=(1/4-1/6)
=2/24
=12 hrs
so, cistern fill in 12 hrs.

Like? Yes | No   

ramanand kumar   8 years AGO

1/4-1/6=1/12
1/12 part in 1 hour
hence to fill completely 12 hour

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Nemichand Suman   8 years AGO

pipe filling per hour = 1/4
pipe empty per hour= 1/6

net filling rate= 1/4-1/6= 1/12
so total time taken for filling cistern =12 Hour

Like? Yes | No   

saurabh shandilya   8 years AGO

because one pie is filling and other pipe empty the cistern therefore 1/T=1/4-1/6

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jaspreet kaur   8 years AGO

pipe a one hour work 1/4 pipe b one hour work -1/6 add them to get the work done

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t Hemanth kumar   8 years AGO

(1/4)-(1/6)= (1/12)
So, the tank's 1/12th portion will be filled in 1 hour and so for the whole tank to be filled, it will take 12 hours

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ooha pravallika   8 years AGO

if it takes 4 hrs then units per day is 3.
and similarly if it empties in 6 hrs then units per day is 2(-).
hence,3-2 is 1 unit.
if for 1 hr it is 1 unit then total of 12 hrs 12 units.

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