Question 1063817
Constant Travel Rates Rule, RT=D, to relate rate R, time T, distance D.


<pre>
                     SPEED      TIME      DISTANCE

Passengertrain        r          3          d

Freighttrain         r-20       3+2         d
</pre>


The description gives enough information to know the times for both trains.  Only two unknown variable to solve:  Passenger train, r, and the overtake-distance, d.


{{{system(r*3=d,(r-20)*5=d)}}}--------two formulas for d.


The question only asks for r and r-20.
{{{3r=5(r-20)}}}