<PRE><B>Question 958094</B>
Two planes just took off from Salt Lake City, UT. The first plane is traveling two times as fast as the second plane. After traveling in the same direction for 4.5 hours, they are 450 miles apart. What is the average speed of each plane?
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let x=speed of 2nd plane
2x=speed of 1st plane
2x-x=x=speed at which the two planes are moving apart
travel time*speed=450
4.5x=450
x=100
2x=200
ave speed of 2nd plane=100 mph
ave speed of 1st plane=200 mph
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