document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=449482>Question 449482</A>: <I><SPAN STYLE=\"word-break: break-all;\"> An airplane takes five hours to travel a distance of 3600 km against the wind. The return trip takes four hours with the wind. What is the rate of the plane in still air, and what is the rate of the wind? Thank you for your help!  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #309204 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=309204\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> plane speed = x mph<BR>\n" );
document.write( "wind speed = y mph\r<BR>\n" );
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document.write( "with wind speed = (x+y)<BR>\n" );
document.write( "against wind speed = (x-y)\r<BR>\n" );
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document.write( "3600/(x+y)=4<BR>\n" );
document.write( "4x+4y=3600<BR>\n" );
document.write( "/4<BR>\n" );
document.write( "x+y=900....................1<BR>\n" );
document.write( " 3600/(x-y)=5<BR>\n" );
document.write( "3600=5x-5y<BR>\n" );
document.write( "x-y=720....................2\r<BR>\n" );
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document.write( "Add (1) +(2)<BR>\n" );
document.write( "2x=1620<BR>\n" );
document.write( "x=810 mph speed of plane<BR>\n" );
document.write( "900-810= 90 mph speed of wind </SPAN>\n" );
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