Question 788731
How many liters,u,  of a L% brine solution must be added to V liters of a H% brine solution to dilute it to an T% solution?
{{{L<T<H}}}.


{{{highlight(V*H/(V+u)=T)}}}


Solve for the unknown u.  You will then have a formula for u.  Plug in the actual given values to compute u.