Question 995210
Let v be the amount of volume of the 60% alcohol to add.  You already know how much volume of the 35% alcohol you will use.  Using v as assigned, the final volume of the solution result will be v+30 milliliters.


The numerator in the following expression is the amount of alcohol multiplied by 100, and the denominator is the amount of volume of final solution.


{{{highlight_green((60v+35*30)/(v+35)=55)}}}
Solve for v.