Question 1023982
<pre>
               rate          time            distance

GOING          64                              200


RETURN         35                              200


Totals                                         400
</pre>


RT=D relates rate, time, and distance.  You need to fill-in the time cells in the table.

<pre>
               rate          time            distance

GOING          64            200/64            200


RETURN         35           200/35             200


Totals                  {{{200/64+200/35}}}           400
</pre>

The average round-trip rate, before any simplifications, is {{{400/(200/64+200/35)}}};
and you will want to simplify this.