Question 1040343
<pre>
                RATE         TIME         DISTANCE
GOING            r            x            d
RETURN           r+k          t            d

{{{system(x=8,t=12,k=20,r=unknownrate,d=unknowndistance)}}}
</pre>


Travel Rates Rule is RT=D relating RATE, TIME, and DISTANCE.


{{{system(rx=d,(r+k)t=d)}}}


{{{rx=(r+k)t}}}


{{{rx=rt+kt}}}


{{{rx-rt=kt}}}


{{{r(x-t)=kt}}}


{{{highlight_green(r=(kt)/(x-t))}}}


--substitute into this one:

{{{d=rx}}}


{{{d=((kt)/(x-t))x}}}


{{{highlight(d=(kxt)/(x-t))}}}