<PRE><B>Question 246283</B>
    How many liters of a 20% salt solution must be added to 42L of a 38% salt solution to get a 28% salt solution?
.
Let x= amount of 20% salt solution added
then
.20x + .38(42) = .28(42+x)
.20x + 15.96 = 11.76 + .28x
15.96 = 11.76 + .08x
4.2 = .08x
52.5 Liters = x
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