Question 987095
<pre>
WHICHWAY      speed      time            distance
going          {{{r[1]}}}       {{{t[1]}}}           {{{r[1]t[1]}}}
returning      {{{r[2]}}}       {{{t[2]}}}           {{{r[2]t[2]}}}
TOTAL                    {{{T}}}
</pre>


The distance going is the same as the distance returning so you have two equations.
{{{system(r[1]t[1]=r[2]t[2],t[1]+t[2]=T)}}}


The unknown variables used are {{{t[1]}}} and {{{t[2]}}}  for going and returning times, in that order.  Solve, and user either direction's distance expression to find the one-way distance.