SOLUTION: How many grams of salt must be added to 40 grams of a 28% salt solution to obtain a 40% salt solution?

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Question 701606: How many grams of salt must be added to 40 grams of a 28% salt solution to obtain a 40% salt solution?
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
(salt)/(salt solution)=0.40

The salt material is 100% salt. The current solution is the lower concentration material at 28% or 0.28. You have 40 grams of this solution and you do not need to know how much resulting solution quantity.
m= grams of salt solid to add,

%28m%2A1.00%2B40%2A0.28%29%2F%28m%2B40%29=0.40

Solve for m.