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Solution Y is 30 percent liquid X and 70 percent water. If 2 kilogram
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08 Nov 2010, 13:02
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Solution Y is 30 percent liquid X and 70 percent water. If 2 kilograms of water evaporate from 8 kilograms of solutions Y and 2 kilograms of solution Y are added to the remaining 6 kilograms of liquid, what percent of this new liquid solution is liquid X? A. 30% B. 33 1/3% C. 37 1/2% D. 40% E. 50% Project PS Butler : Question #106 Subscribe to get Daily Email  Click Here  Subscribe via RSS  RSS
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Re: Solution Y is 30 percent liquid X and 70 percent water. If 2 kilogram
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06 Apr 2012, 12:19
rovshan85 wrote: Solution Y is 30% liquid X and 70 percent water. If 2 kilograms of water evaporate from 8 kg of solution Y and 2 kg of solution Y are added to the remaining 6 kg of liquid, what percent of this new solution is liquid X?
a. 30 b. 33 1/3 c. 37 1/2 d. 40 e. 50
What is the easiest way to approach this type of problem and solve under 2 min. In 8 kilograms of solution Y there are 0.3*8=2.4 kilograms of solution X; After 2 kilograms of water are replaced by 2 kilograms of solution Y, to the existing 2.4 kilograms of solution X, 0.3*2=0.6 kilograms of solution X are added, so in the new solution of 8 kilograms there are 2.4+0.6=3 kilograms of solution X, which is 3/8*100=37.5% of this new solution. Answer: C.
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Re: Solution Y is 30 percent liquid X and 70 percent water. If 2 kilogram
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08 Nov 2010, 13:16
At the beggining, you have 8KG of solution Y, i.e.
70% * 8KG = 5,6 KG of Water 30% * 8KG = 2,4 KG of X
2KG of water evaporate:
5,6KG  2KG = 3,6KG of Water 2,4KG of X
2KG of liquid are added:
3,6KG + 2*0,70 = 5KG of Water 2,4KG + 2*0,30 = 3 KG of X
So you have 3KG of X in 8KG (3 + 5) solution. Therefore X concentration is 3/8 = 37,5%




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Re: Solution Y is 30 percent liquid X and 70 percent water. If 2 kilogram
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08 Nov 2010, 23:01
Answer:CTook time to solve this one, the statement 2 kilograms of solution Y are added to the remaining 6 kilograms of liquid was confusing to me. After thinking more deeply, it was clear to me that new 2 kg of solution Y will also be 30% liquid X and 70% water, and then I was able to get the answer. That was a bit tricky and nice question. Kudos +1 for posting the question
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Re: Solution Y is 30 percent liquid X and 70 percent water. If 2 kilogram
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08 Nov 2010, 23:25
Initially you start with 8kg of solution which has 2.4kg of X and 5.6kg of water Post evaporation : 2.4kg of X and 3.6kg of water Now we add back 2kg of Y > 1.4Kg water + 0.6Kg X So we have left 5Kg Water & 3Kg X Percentage concentration is (3/5)*100 or 37.5%
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Re: Solution Y is 30 percent liquid X and 70 percent water. If 2 kilogram
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08 Nov 2010, 23:43
shrouded1 wrote: Initially you start with 8kg of solution which has 2.4kg of X and 5.6kg of water Post evaporation : 2.4kg of X and 3.6kg of water Now we add back 2kg of Y > 1.4Kg water + 0.6Kg X So we have left 5Kg Water & 3Kg X
Percentage concentration is (3/5)*100 or 37.5% Yea, that's exactly how I solved but you know at first I was kinda adding 2 to 6 kg without considering liquid X and water's concentration within 2 kg being added.
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Re: Solution Y is 30 percent liquid X and 70 percent water. If 2 kilogram
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Re: Solution Y is 30 percent liquid X and 70 percent water. If 2 kilogram
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11 Dec 2011, 22:43
Initially we have 8kg of solution which has 3/10 0f 8= 2.4kg of X and 7/10 of 8 = 5.6kg of water after evaporation : 2.4kg of X and 3.6kg of water Now we added 2kg of solution Y > 7/10 of 2=1.4Kg water + 3/10 0f 2 =0.6Kg X So we have left 5Kg Water & 3Kg X
Percentage concentration is (3/5)*100 or 37.5%



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Re: Solution Y is 30 percent liquid X and 70 percent water. If 2 kilogram
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02 Jun 2012, 08:51
Solution Y total = 8 Liq x = 30% (8) = 2.4
Added 2 kg of Solution Y Liq x = 30% (2) = 0.6
Final Solution wil have = (2.4 + 0.6) = 3 kg of Liq x
3/8 = 37.5%



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Re: Solution Y is 30 percent liquid X and 70 percent water. If 2 kilogram
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26 Aug 2013, 20:32
rovshan85 wrote: Solution Y is 30 percent liquid X and 70 percent water. If 2 kilograms of water evaporate from 8 kilograms of solution Y and 2 kilograms of solution Y are added to the remaining 6 kilograms of liquid, what percent of this new solution is liquid X?
A. 30% B. 33 1/3% C. 37 1/2% D. 40% E. 50%
What is the easiest way to approach this type of problem and solve under 2 min. 1. The net effect of 2 kg of water evaporating and adding 2 kg of the solution is removing (2 + 1.4 = 0.6) 0.6 kg of water and adding 0.6 kg of liquid 2 Therefore the changed solution contains, 2.4 + 0.6 = 3 kg of liquid and 5.60.6==5 kg of water. 3. Percentage of liquid is 3/8 * 100 % = 37 1/2 %
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Re: Solution Y is 30 percent liquid X and 70 percent water. If 2 kilogram
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05 Jan 2016, 04:55
rtaha2412 wrote: Solution Y is 30 percent liquid X and 70 percent water. If 2 kilograms of water evaporate from 8 kilograms of solutions Y and 2 kilograms of solution Y are added to the remaining 6 kilograms of liquid, what percent of this new liquid solution is liquid X?
A. 30% B. 33 1/3% C. 37 1/2% D. 40% E. 50% The best way to solve these problems is to take one step at a timeInitial: 8 kg Solution Y This means Solution X = 2.4 kg, Water = 5.6 kg Step 2: 2 kg of water is evaporated. Left over: Solution X = 2.4 kg and Water = 3.6 kg Step 3: 2 kg of Solutoin Y is added Or, 0.6 kg of Solution X and 1.4 kg of water is added Final: Solution X = 3, Water = 5 % of solution X = 3/8 * 100 = 37.5% Option C



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Re: Solution Y is 30 percent liquid X and 70 percent water. If 2 kilogram
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03 May 2016, 06:47
rtaha2412 wrote: Solution Y is 30 percent liquid X and 70 percent water. If 2 kilograms of water evaporate from 8 kilograms of solutions Y and 2 kilograms of solution Y are added to the remaining 6 kilograms of liquid, what percent of this new liquid solution is liquid X?
A. 30% B. 33 1/3% C. 37 1/2% D. 40% E. 50% Hi, I like using a table for mixture problems. This is what I came up with (see attachement):
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Re: Solution Y is 30 percent liquid X and 70 percent water. If 2 kilogram
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Updated on: 28 Feb 2018, 21:08
Solution Y is 30 percent liquid X and 70 percent water. If 2 kilograms of water evaporate from 8 kilograms of solutions Y and 2 kilograms of solution Y are added to the remaining 6 kilograms of liquid, what percent of this new liquid solution is liquid X?
A. 30% B. 33 1/3% C. 37 1/2% D. 40% E. 50%
let x=% of liquid X in new solution .3*8+.3*2=x(6+2) x=3/8=37.5% C
Originally posted by gracie on 18 Jul 2016, 19:23.
Last edited by gracie on 28 Feb 2018, 21:08, edited 1 time in total.



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Re: Solution Y is 30 percent liquid X and 70 percent water. If 2 kilogram
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22 Sep 2018, 05:52
DS00 wrote: rtaha2412 wrote: Solution Y is 30 percent liquid X and 70 percent water. If 2 kilograms of water evaporate from 8 kilograms of solutions Y and 2 kilograms of solution Y are added to the remaining 6 kilograms of liquid, what percent of this new liquid solution is liquid X?
A. 30% B. 33 1/3% C. 37 1/2% D. 40% E. 50% Hi, I like using a table for mixture problems. This is what I came up with (see attachement): I also used the similar approach. To Sum up: Initial 8 kilograms of Y consist of 2.4 kg X and 5.6 kg water. We then lose 2 kg water to evaporation, so we are down to 3.6 kg water. The final step adds 2 kg Y, which consists of .6 kg X and 1.4 kg water. Therefore, the final mixture contains 3 kg X and 5 kg water. 3/8 = 37.5%.



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Re: Solution Y is 30 percent liquid X and 70 percent water. If 2 kilogram
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13 Dec 2018, 23:02
30% of 8 + 30% of 2 = 3 = X X/T= 3/8 = 0.375 =37.5%
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Re: Solution Y is 30 percent liquid X and 70 percent water. If 2 kilogram
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29 Dec 2018, 01:52
rtaha2412 wrote: Solution Y is 30 percent liquid X and 70 percent water. If 2 kilograms of water evaporate from 8 kilograms of solutions Y and 2 kilograms of solution Y are added to the remaining 6 kilograms of liquid, what percent of this new liquid solution is liquid X? A. 30% B. 33 1/3% C. 37 1/2% D. 40% E. 50% Project PS Butler : Question #106 Subscribe to get Daily Email  Click Here  Subscribe via RSS  RSS8 kg of the solution contains (8*0.3) kg = 2.4 kg of X again, 2 kg of the add solution which is added will have 2*0.3 = 0.6 kg of X Total final volume of the solution = 8 kg Hence, % of X = (2.4+0.6)/8*100 = 3/8 * 100 =3* 12.5 = 37.5 % Hence C)



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Re: Solution Y is 30 percent liquid X and 70 percent water. If 2 kilogram
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02 Jan 2019, 19:22
Hello!
Tricky question, these topics is very challenging for me.
Is it possible to solve it with weighted averages?
Kind regards!




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