Question 649630
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Hi,
What quantity{{{highlight(x)}}} of a 80% acid solution must be mixed with a 
40% solution to produce 600 mL of a 55% solution?
 {{{.80x + .40(600-x) = .55*600}}}
        .40x = .15*600 = 90
           x = 90/.40
           x = 225ml