Question 838391
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Hi,
How much of the 85% alcohol mixture(15% water) and pure water
to make 765 mL of a 30% alcohol solution (70% water)
Let x represent the ml of water needed to be added
          water = water
 {{{.15*(765-x)  + x = .70*765)}}}
     {{{x = (.55*765)/.85 }}}  x = 495ml of water need to be added