<PRE><B>Question 259889</B>
The planes will be going the same distance but not a tthe ssame time
rt=d
rate*time=distance
eg 60 mph*2 hours =120 miles
rt=rt
we know the rates ( speeds)
564*t=744*(t-1/2)
564t=744t-744*1/2
Your son should be able to finish this.
Usually the hard part is setting up the equations.
t=31/15 
2 hours 1/15 hour 
1/15 of an hour is 4 minutes
2hr 4 minutes
that needs to be convert to hours.
t is the amount of time for the plane at 564 mph
t-1/2 is the other plane

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