document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=974123>Question 974123</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A plane can travel 470mph with the wind and 390mph against the wind.  What is the speed of the plane if the air is still? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #596140 by </B><A HREF=/tutors/aboutme.mpl?userid=lwsshak3><B>lwsshak3(11628)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=lwsshak3><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=596140\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A plane can travel 470mph with the wind and 390mph against the wind. What is the speed of the plane if the air is still?<BR>\n" );
document.write( "***<BR>\n" );
document.write( "let x=speed of plane in still air<BR>\n" );
document.write( "let c=speed of wind<BR>\n" );
document.write( "x+c=speed of plane downwind<BR>\n" );
document.write( "x-c=speed of plane against the wind<BR>\n" );
document.write( "..<BR>\n" );
document.write( "x+c=470<BR>\n" );
document.write( "x-c=390<BR>\n" );
document.write( "add<BR>\n" );
document.write( "2x=860<BR>\n" );
document.write( "x=430<BR>\n" );
document.write( "What is the speed of the plane if the air is still? 430 mph </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );