Question 1160139
<pre>
                 SPEED           TIME             DISTANCE
Scooter         2r+4             18/(2r+4)          18
Bicycle          r               7/r                 7
</pre>
The two times were described as equal.
{{{highlight_green(18/(2r+4)=7/r)}}}


{{{9/(r+2)=7/r}}}


{{{7(r+2)=9r}}}


{{{7r+14=9r}}}


{{{14=2r}}}


{{{highlight(r=7)}}}---------bicycle
-
{{{2r+4=highlight(18)}}}----------the scooter