SOLUTION: Hi, I am trying to complete a practice test for my Algebra class but I need help solving the following problem: How much water must be evaporated from 64 oz of a 10% salt soluti

Question 519224: Hi, I am trying to complete a practice test for my Algebra class but I need help solving the following problem:
How much water must be evaporated from 64 oz of a 10% salt solution to make a 2% salt solution?
If possible, could you also show me how you got the answer.
Thank you.
Lia M.
Answer by mananth(16946) (Show Source): You can put this solution on YOUR website!
Firstly if you evaporate 10% solution the concentration will increase. It wont decrease.
The other way is possible
initial conc 2 % final 10%
water to be evaporated be x

when x evaporates there is 64 - x left,
which has 90% water
2% of 64 = 1.28 oz is salt,
64 - 1.28 = 62.72oz is water.

62.72 - x = 0.9 (64 - x)
62.72 - x = 57.6 - 0.90x
-0.1x = -5.12
x = 51.2 oz of water
m.ananth@hotmail.ca
RELATED QUESTIONS
I have been studying all day and doing practice problems from my math book to get me... (answered by Jeef Gorrdon,richwmiller)

Hi. I need help solving this problem for my physics class. I am a bit rusty on solving... (answered by jojo14344,scott8148)

Hi, I'm taking an online college algebra class but can't quite recall all the review... (answered by stanbon)

Hi, In my Algebra II class we are working on Solving Quadratic Equations by graphing. I... (answered by venugopalramana)

Hi thank you for aking the time to helpme with this, I have a writingassignment and I... (answered by ankor@dixie-net.com)

Hi I need help solving this problem in College Algebra B. I have this on my test and need (answered by Alan3354,MathTherapy)

I am trying to help my daughter Ember in her algebra class. How would you solve and... (answered by stanbon)

Hi, I am taking an algebra class online and need help. I do not have the barcode of the... (answered by checkley77)

Please Please I need help solving a problem in algebra. The problem is that I am trying... (answered by scott8148)