Question 1131014
<pre>
              SPEED        TIME       DISTANCE

GOING         r             8         d
 
RETURN        r+21          5         d
</pre>

{{{system(8r=d,5(r+21)=d)}}}



{{{8r=5r+105}}}
{{{3r=105}}}
{{{r=35}}}



{{{d=35*8}}}
{{{highlight(d=280)}}}