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8 liters of solution is removed from 20% milk solution and 8 liters of

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8 liters of solution is removed from 20% milk solution and 8 liters of  [#permalink]

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New post Updated on: 12 Oct 2016, 00:31
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8 liters of solution is removed from 20% milk solution and 8 liters of water is added to the solution. The resulting solution has 16% milk in it. What was the initial quantity of the 20% milk solution?

Originally posted by RidhimaNigam on 12 Oct 2016, 00:14.
Last edited by Bunuel on 12 Oct 2016, 00:31, edited 1 time in total.
Renamed the topic.
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Re: 8 liters of solution is removed from 20% milk solution and 8 liters of  [#permalink]

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New post Updated on: 13 Oct 2016, 19:56
Corrected solution(apologies for posting wrong solution previously)

Change in concentration of milk is 4%(down from 20% to 16%)
This change is concentration happens when 8 liters of the solution is replaced(with pure water)
If we consider x to be total volume of the solution.
From the given information, we can frame equation

20/100(x-8) = 16/100(x)
5(x-8) = 4x or x=40
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Originally posted by pushpitkc on 12 Oct 2016, 01:05.
Last edited by pushpitkc on 13 Oct 2016, 19:56, edited 1 time in total.
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Re: 8 liters of solution is removed from 20% milk solution and 8 liters of  [#permalink]

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New post 12 Oct 2016, 01:37
Method 1:

Allegation method.

Concentration of Alcohol in original sol - 20%

Concentration of Alcohol in water -- 0%

Concentration of Alcohol in final sol -- 16%

After applying allegation as shown in figure they have to be mixed in 4:1 part

1 part is given as 8 ltr, so total initial volume is 5 part = 5*8 = 40 Ltrs



Method 2:

Using Algebra

Concentration of Alcohol in original sol - 20%

Volume of alcohol - .2*X (Say the initial volume is X ltrs)

When we remove 8 ltrs from this liquid - .2*8 alcohol also gets removed.

Final concentration of alcohol sol is given as 16%

Alcohol %age in final solution = (.2*x - .2*8)/x = .16

Solving for X, we get X = 40

HTH
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Re: 8 liters of solution is removed from 20% milk solution and 8 liters of  [#permalink]

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New post 12 Oct 2016, 10:45
RidhimaNigam wrote:
8 liters of solution is removed from 20% milk solution and 8 liters of water is added to the solution. The resulting solution has 16% milk in it. What was the initial quantity of the 20% milk solution?

Let x be the initial volume

then , per question

20%(x-8)= 16% of x (as %ge of milk remains same irrespective of volume)
thus x= 40 lts..
Ans 40 lts. :)
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Re: 8 liters of solution is removed from 20% milk solution and 8 liters of  [#permalink]

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New post 12 Oct 2016, 14:14
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8 liters of solution is removed from 20% milk solution and 8 liters of water is added to the solution.
The resulting solution has 16% milk in it. What was the initial quantity of the 20% milk solution?

let x=initial quantity
.2x-.2*8=.16x
x=40 liters
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Re: 8 liters of solution is removed from 20% milk solution and 8 liters of  [#permalink]

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New post 08 Apr 2018, 04:17
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Re: 8 liters of solution is removed from 20% milk solution and 8 liters of &nbs [#permalink] 08 Apr 2018, 04:17
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