Question 1083006
<pre>
              SPEED       TIME       DISTANCE 

TRAIN          r+40       t            1200

BUS            r          t+t/2        1200
</pre>


{{{r(3t/2)=1200}}}
{{{1200(2/3)(1/r)=t}}}
{{{t=800/r}}}


-

{{{(r+40)(800/r)=1200}}}


{{{(r+40)/r=12/8}}}
{{{(r+40)/r=3/2}}}
{{{2(r+40)=3r}}}
{{{2r+80=3r}}}
{{{r=80}}} --- {{{r+40=120}}}
-
Bus, 80 km/h
Train, 120 km/h
(t=10 hours for the train)