document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=732448>Question 732448</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A certain aircraft can fly 630 miles with the wind in 3 hours and travel the same distance against the wind in 7 hours. What is the speed of the wind? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #447850 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=447850\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 630 miles in 3 hours<BR>\n" );
document.write( "with wind speed = 210 mph\r<BR>\n" );
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document.write( "630 in 7 hours\r<BR>\n" );
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document.write( "against wind speed = 630/7 = 90 mph\r<BR>\n" );
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document.write( "plane speed = x<BR>\n" );
document.write( "wind speed = y<BR>\n" );
document.write( "x+y = 210<BR>\n" );
document.write( "x-y=90\r<BR>\n" );
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document.write( "add up the equations<BR>\n" );
document.write( "2x=300<BR>\n" );
document.write( "/2<BR>\n" );
document.write( "x= 150 mph<BR>\n" );
document.write( "so wind speed = 60 mph </SPAN>\n" );
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