answer: 37 1/2%
thanks for the help
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solution X and Y
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charmaine
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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 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?
answer: 37 1/2%
thanks for the help
answer: 37 1/2%
thanks for the help
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superbrat123
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In 8 kilogram solution of Y
x=30% of 8 = 2.4, water = 70% of 8 = 5.6
Now, 2 kilogram of water is evaporated => 5.6-2.0 = 3.6
In 2 kilogram solution of Y, x=30%of2 = 0.6, water = 70%of2=1.4
In the final solution, we have
x = 2.4+0.6, total water = 3.6+1.4
x as percent of x+water = 3.0/3.0+5.0 = 3/8 = 37.5%
x=30% of 8 = 2.4, water = 70% of 8 = 5.6
Now, 2 kilogram of water is evaporated => 5.6-2.0 = 3.6
In 2 kilogram solution of Y, x=30%of2 = 0.6, water = 70%of2=1.4
In the final solution, we have
x = 2.4+0.6, total water = 3.6+1.4
x as percent of x+water = 3.0/3.0+5.0 = 3/8 = 37.5%
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cramya
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Convert the kilograms to grams (1kg = 1000g) Since we are asked percent it doesnt change. Even if the question was what kg of x is present in the final solution its an easy divide by 1000
It may be easy to work with in 2 minutes. Just my opinion!! Good luck!
It may be easy to work with in 2 minutes. Just my opinion!! Good luck!
Most importantly, we have to concentrate on what is being asked! If you concentrate solely on X, you can solve this question fast.
Consider the attached table, which helped me out a lot to grasp this concept.
From the table we gain the equation:
0.3 (8) + 0.3 (2) = 0.3 (8+2) = 0.3 (10) = 3
8 kg of solution Y contains 3 kg of solution X:
3/8 = 37.5 %
Hope this helps!
Consider the attached table, which helped me out a lot to grasp this concept.
From the table we gain the equation:
0.3 (8) + 0.3 (2) = 0.3 (8+2) = 0.3 (10) = 3
8 kg of solution Y contains 3 kg of solution X:
3/8 = 37.5 %
Hope this helps!
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- Mixture.xls
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GMATGuruNY
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The water that is being replaced is 2/8 = 25% of the total solution. We are replacing this 25% with solution Y. Thus, the percentage of liquid X in the total solution is going to increase by 25%:
1.25*30 = 37.5.
The correct answer is D.
Similarly, if the water being replaced were 4/8 = 50% of the total solution, the percentage of liquid X would increase by 50% in the resulting solution. The resulting solution would be 1.5*30 = 45% X and 55% water.
1.25*30 = 37.5.
The correct answer is D.
Similarly, if the water being replaced were 4/8 = 50% of the total solution, the percentage of liquid X would increase by 50% in the resulting solution. The resulting solution would be 1.5*30 = 45% X and 55% water.
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Followed here and elsewhere by over 1900 test-takers.
I have worked with students based in the US, Australia, Taiwan, China, Tajikistan, Kuwait, Saudi Arabia -- a long list of countries.
My students have been admitted to HBS, CBS, Tuck, Yale, Stern, Fuqua -- a long list of top programs.
As a tutor, I don't simply teach you how I would approach problems.
I unlock the best way for YOU to solve problems.
For more information, please email me (Mitch Hunt) at [email protected].
Student Review #1
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Student Review #3
