Question 1196702
The example may be as weight per volume.


Mixing 25% with 80% to make 10 ml. of 69%


If x of the 80%, then
{{{80x+25(10-x)=69*10}}}
Solve this for x.


{{{80x+25*10-25x=69*10}}}

{{{(80-25)x=69*10-25*10}}}

{{{(80-25)x=10(69-25)}}}

{{{highlight(x=10((69-25)/(80-25)))}}}

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