document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=359536>Question 359536</A>: <I><SPAN STYLE=\"word-break: break-all;\"> If a plane can travel 470 miles per hour with the wind and 410 miles per hour against the wind, find the speed of the plane in the still air? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #256533 by </B><A HREF=/tutors/aboutme.mpl?userid=mananth><B>mananth(16946)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=mananth><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/cgi-bin/show-face.mpl?user=mananth><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=256533\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Ilet x be the speed of the plane in still air<BR>\n" );
document.write( "y be the speed of the wind\r<BR>\n" );
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document.write( "Speed of plane with wind = x + y<BR>\n" );
document.write( "Speed of plane against wind= x - y.\r<BR>\n" );
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document.write( "So we have the following system of equations:\r<BR>\n" );
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document.write( "{ x + y = 470. .  . . .1<BR>\n" );
document.write( "{ x - y = 410. .  . . 2\r<BR>\n" );
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document.write( "Adding both we get 2x = 880<BR>\n" );
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document.write( "x = 440.<BR>\n" );
document.write( "Therefore, the speed of the plane in still air is 440mph.<BR>\n" );
document.write( "...<BR>\n" );
document.write( "m.ananth@hotmail.ca<BR>\n" );
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