SOLUTION: I cannot wrap my brain around word problems. Please help me!! How much water must be evaporated from 16 oz of a 2% salt solution to make a 4% salt solution? To obtain a solut

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Question 852413: I cannot wrap my brain around word problems. Please help me!!
How much water must be evaporated from 16 oz of a 2% salt solution to make a 4% salt solution?
To obtain a solution that is 4% salt solution, ____ oz of water must be evaporated.
Thank you in advance
Answer by josgarithmetic(39618) About Me  (Show Source):
You can put this solution on YOUR website!
Amount of salt will be the same before and after evaporation.
Amount of salt is 16*(0.02).

Amount of salt solution at the beginning is 16 ounces. Most of this is water, and some of it is salt. The WATER WILL DECREASE THROUGH EVAPORATION.

At start, fraction of the solution being salt is %2816%280.02%29%29%2F16=0.02.

After the needed evaporation, the numerator is unchanged, but the denominator must be decreased; and the resulting fraction must equal 0.04.

From that, do you know what to do?