Question 789956
The 200 mph plane traveled for h+2 hours, which shows the two-hour headstart.  The 500 mph plane traveled for h hours.  Are you given more information than you described in your help-request?  Your five tutors could well have found the problem description to be incomplete, which is why they could not solve this problem.  WHERE is the information about distance?  None!


About the best you can analyze is like this:  
Let the distance, still not given nor described, be d, and UNKNOWN for time.
Let the time for the 500 mph plane be h, UNKNOWN time in hours.


When the two planes reach the same place in their travel, we have
{{{highlight(500*h=200(h+2))}}}, which is simply EQUATING their traveled distance.  Suddenly this appears to be solvable.  That is one equation with only one unknown, d.


{{{500h=200h+400}}}
{{{500h-200h=200h+400-200h}}}
{{{300h=400}}}
{{{h=4/3}}} HOURS, which is 1 hour 20 minutes.


With the time now known, you can compute the distance. Take your pick which expression:
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500(4/3)=667 miles
Or
200(2+4/3)=667 miles
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