<PRE><B>Question 455082</B>
Let x = the no. gallons of a 60% salt solution that must be mixed with 30 gallons of a 13% solution to obtain a solution that is 50% salt

.6x + 30(.13) = .5(30 + x)
   .6x + 3.9  = 15 + .5x
         .1x  = 11.1
           x  = 111

111 gallons of a 60% salt solution that must be mixed with 30 gallons of a 13% solution to obtain a solution that is 50% salt.

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