document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=518397>Question 518397</A>: <I><SPAN STYLE=\"word-break: break-all;\"> a plane flies 405 miles with the wind and 315 miles against the wind in the same length of time. if the speed of the with is 20 mph, then find the speed of the plane in 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 #345167 by </B><A HREF=/tutors/aboutme.mpl?userid=Alan3354><B>Alan3354(69443)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Alan3354><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=Alan3354><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=345167\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> t = d/r<BR>\n" );
document.write( "t = 405/(a+20) = 315/(a-20)<BR>\n" );
document.write( "9/(a+20) = 7/(a-20)<BR>\n" );
document.write( "9(a-20) = 7(a+20)<BR>\n" );
document.write( "a = 160 mi/hr<BR>\n" );
document.write( "It's airspeed, not \"speed of the plane in still air\"<BR>\n" );
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