<PRE><B>Question 352346</B>
choose an arbitrary &quot;step&quot; size and calculate the average speed


the 1st man rides the horse 3 miles ___ this takes 3/5 hour


the 2nd man reaches the horse in 1 hour ___ the 1st man has 2/5 hour head start


r * t = d ___ 3[t + (2/5)] = 5t ___ 6/5 = 2t ___ 3/5 = t


so it takes 8/5 hr to travel 6 mi , where the two men and the horse are together to start another &quot;step&quot;
___ the average speed is [6 / (8/5)] or 15/4 mph ___ this is constant ,REGARDLESS of step size


you can see from the calculations , that both men walk and ride an equal distance


for the total trip ___ t = d / r ___ t = 20 / (15/4) = 16/3</PRE>