Question 949597
<b>EDIT:  This IS the solution process, and the formula can be evaluated at the end if needed for any final answer.</b>
(Note:  One omission adjustment)


Rate of "other bus", r
Rate of "one bus", r-10
t, time when meet
d, distance separation at the start
condition:  two busses going toward each other.



___________________rate____________time___________distance
One bus____________r-10____________t______________(r-10)*t
Other bus___________r______________t______________(r*t)
Total_______________________________________________d


Only r is unknown.


{{{(r-10)t+rt=d}}}
{{{rt-10t+rt=d}}}
{{{2rt-10t=d}}}
{{{2rt=d+10t}}}
{{{highlight(r=(d+10t)/(2t))}}}------(adjusted)


You can derive {{{r-10}}}.
You can substitute the given values to compute r and r-10.