Question 908923
Let T = any target value as percent antifreeze.  Note that {{{0<=T<100}}}.


v = volume of 100% antifreeze to add, measured in liters
T will be a constant, but used separately as two values.


{{{highlight_green((100*v)/(v+5)=T)}}};
Solve this for v.  You will then use two different values of T to evaluate the minimum and maximum specified amounts v to add.


{{{100v=T(v+5)}}}
{{{100v=Tv+5T}}}
{{{100v-Tv=5T}}}
{{{v(100-T)=5T}}}
{{{highlight(v=(5T)/(100-T))}}}
-
Evaluate v for T=60 and for T=80.