Question 1002772

 if both solutions have the same concentration of alcohol in water, then we have a proportion
 
12 milliliters of alcohol : 15 milliliters of water=x milliliters of alcohol : 25 milliliters of water

or simply
{{{12/15=x/25}}}...solve for {{{x}}}

{{{12*25=x*15}}}

{{{300=15x}}}

{{{x=300/15}}}

{{{x=20}}}

another solution must contain {{{20}}} milliliters of alcohol