SOLUTION: how much water must be evaporated from 32 ounces of a 4% salt solution to produce a 6% salt solution?

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Question 12470: how much water must be evaporated from 32 ounces of a 4% salt solution to produce a 6% salt solution?
Answer by Earlsdon(6287) (Show Source):
You can put this solution on YOUR website!
Let's see, 32 oz of 4% salt solution is 96% water and 6% salt solution is 94% water. Since we are not removing any salt, the question can be rephrased: How much water must be evaporated from 32 oz of 96% water solution to produce a 94% water solution? Change the percentages to decimals. 94% = 0.94, 96% = 0.96, 100% = 1
The equation is now in terms of water rather than salt:

Subtract 30.08 from both sides.
Add x to both sides.
Divide both sides by 0.06

So, 10.67 oz of water must be evaporated. This is one third of the original 32 oz. of solution.