Question 1122045
First question of your description:
<pre>
DRIVER/PERSON      SPEED         TIME        DISTANCE

MOTORIST             r             5           d

BUS                  r+30          3           d
</pre>
{{{5r=3(r+30)}}}

{{{5r=3r+90}}}

{{{highlight(r=45)}}}----------speed of motorist

-

{{{r+30=highlight(75)}}}--------speed of bus