Question 1011608
<pre>
GOTO        40        d/40         d
BACK        50        d/50         d
Total                 1
</pre>


{{{highlight(d/40+d/50=1)}}};
Solve for d and you are done  (after round to nearest mile).



Denominators:
2*2*2*5, and 2*5*5;


{{{(d/40)(5/5)+(d/50)(4/4)=1}}}
{{{5d/200+4d/200=1}}}
{{{(9d)/200=1}}}
{{{d=200/9}}}
Rounds to 22 miles.