document.write( "Question 528206: A fighter plane and a helicopter set off from airbase A at the same time. The helicopter travels on a bearing of 152 degrees and the fight plane travels on a bearing of 242 degrees at three times the speed. They arrive at bases B and C respectively after 2 hours. If B and C are 1200 km apart, find the average speed of the helicopter ? \n" ); document.write( "
Algebra.Com's Answer #349341 by ankor@dixie-net.com(22740)\"\" \"About 
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A fighter plane and a helicopter set off from airbase A at the same time.
\n" ); document.write( "The helicopter travels on a bearing of 152 degrees and the fight plane travels on a bearing of 242 degrees at three times the speed.
\n" ); document.write( " They arrive at bases B and C respectively after 2 hours.
\n" ); document.write( " If B and C are 1200 km apart, find the average speed of the helicopter ?
\n" ); document.write( ":
\n" ); document.write( "Let s = speed of the helicopter
\n" ); document.write( "then 2s = distance traveled by the helicopter
\n" ); document.write( ":
\n" ); document.write( "Let 3s = speed of the fighter
\n" ); document.write( "then 6s = distance traveled by the fighter
\n" ); document.write( ";
\n" ); document.write( "Conveniently: 242 - 152 = 90 degrees, a right triangle problem with the hypotenuse = 1200
\n" ); document.write( ":
\n" ); document.write( "(2s)^2 + (6s)^2 = 1200^2
\n" ); document.write( "4s^2 + 36s^2 = 1440000
\n" ); document.write( "40s^2 = 1440000
\n" ); document.write( "Divide both sides by 40
\n" ); document.write( "s^2 = 36000
\n" ); document.write( "s = \"sqrt%2836000%29\"
\n" ); document.write( "s = 189.7 mph is the helo speed \n" ); document.write( "
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