Question 1159919
Mixture A,  40%
Mixture B,  65%
Mixture wanted, 40 ounces of 60%


y, amount of mixture B of 65%
40-y, amount of mixture A of 40%


{{{65y+40(40-y)=60*40}}}
-
{{{65y+40*40-40y=60*40}}}
{{{65y-40y=60*40-40*40}}}
{{{(65-40)y=40(60-40)}}}
{{{y=40((60-40)/(65-40))}}}------------and you can finish from here.










The example can NOT be salt dissolved in water!   A physical dry mixture, would be possible, but not a salt solution in water of over ~26%.  Other solvents for dissolving salt better than water - not likely