Question 1011507
<pre>
            speed       time            distance

GOING         r         {{{3&1/4-1/2}}}        140

RETURN      r-10        ()               140

Total                   (?)              280
</pre>


Using RT=D basic travel rate rule, r can be found and applied to fill the other cells.
{{{r=140/(3&1/4-1/2)}}}

<pre>
            speed             time            distance

GOING         {{{560/11}}}       {{{2&3/4}}}        140

RETURN      {{{450/11}}}         {{{(154/11)}}}       140

Total                         {{{165/11}}}          280
</pre>


Average distance accounting only for time traveling,
{{{280/(165/11)}}}
{{{280/15=56/3}}}
{{{highlight(18&2/3)}}}---average speed for traveling time only




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Be aware, I did not check this for mistakes.