<PRE><B>Question 633034</B>
Let them meet at distance x from Denver
LA to Denver - speed = 450 mph
Denver to LA = 520 mph  ( 30 minutes later)

Total distance = 850 miles

d=rt

When the second plane starts  the first plane has already traveled 450*1/2 = 225 miles

so the distance between them will be 625 miles

add up their speeds = 520+450 = 970 mph

time = d/r
time = 625/970
= 0.64 hours

Distance from denver = 0.64*520= 334.8 miles

m.ananth@hotmail.ca


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