Question 590288
    How many kilograns of water must be evaporated from 50 kg of a 10% salt solution to obtain a 15% salt solution?
.
Let x= amount (kilograms) of water evaporated
then
.10(50) = .15(50-x)
5 = 7.5 - .15x
-2.5 = -.15x
2.5 = .15x
2.5/.15 = x
250/15 = x
50/3 = x
16.67 kilograms = x