document.write( "Question 551208: Two planes start from Chicago at the same time and fly in opposite directions, one averaging a speed of 40mi/hr greater than the other. If they are 2000 miles apart after 5hours, find their average speeds. Please thank you. \n" ); document.write( "
Algebra.Com's Answer #359535 by mananth(16946)\"\" \"About 
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first plane speed = x
\n" ); document.write( "second plane speed = x+40\r
\n" ); document.write( "\n" ); document.write( "going away from each other so add up speeds
\n" ); document.write( "x+x+40
\n" ); document.write( "=2x+40\r
\n" ); document.write( "\n" ); document.write( "t=5 hours
\n" ); document.write( "d=2000\r
\n" ); document.write( "\n" ); document.write( "5=2000/(2x+40)\r
\n" ); document.write( "\n" ); document.write( "10x+200=2000
\n" ); document.write( "10x=2000-200
\n" ); document.write( "10x=1800
\n" ); document.write( "/10
\n" ); document.write( "x= 180 mph speed of first plane
\n" ); document.write( "speed of second plane = 180 +4= 220 mph\r
\n" ); document.write( "\n" ); document.write( "Happy New Year
\n" ); document.write( "m.ananth@hotmail.ca
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