document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=668525>Question 668525</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A light private plane can fly 120 mph in still air. Flying against the wind, the plane can fly 320 miles in the same time it requires to fly 640 miles with the wind. Find the rate of the wind. \r<BR>\n" );
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document.write( "If w represents the rate of the wind, which expression represents the time it takes the plane to travel the 640 miles with the wind?<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #415691 by </B><A HREF=/tutors/aboutme.mpl?userid=lynnlo><B>lynnlo(4176)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=lynnlo><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=415691\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> d=rt OR    t=d/r<BR>\n" );
document.write( "t=320/(120-w)<BR>\n" );
document.write( "t=640/(120+w)<BR>\n" );
document.write( "320/(120-w)=640/(120+w)<BR>\n" );
document.write( "640(120-w)=320(120+w)<BR>\n" );
document.write( "76,800-640w=38,400+320<BR>\n" );
document.write( "-640w-320w=38,400-76,800<BR>\n" );
document.write( "-980w=-38,400<BR>\n" );
document.write( "w=-38,400/-960<BR>\n" );
document.write( "the wind speed is 40 mph </SPAN>\n" );
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