document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=79382>Question 79382</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A plane flies 480 miles with the wind and 320 miles against the wind in the same length of time. If the speed of the wind is 28mph, what is 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 #57017 by </B><A HREF=/tutors/aboutme.mpl?userid=checkley75><B>checkley75(3666)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=checkley75><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=57017\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> USING THE FORMULA (DISTANCE=RATE*TIME) WE HAVE:<BR>\n" );
document.write( "480=(R+28)T & T=480/(R+28)<BR>\n" );
document.write( "320=(R-28)T & T=320/(R-28)<BR>\n" );
document.write( "SEEING AS THE TIMES ARE THE SAME WE HAVE THE EQUATION:<BR>\n" );
document.write( "480/(R+28)=320/(R-28) NOW WE CROSS MULTIPLY & GET<BR>\n" );
document.write( "480(R-28)=320(R+28)<BR>\n" );
document.write( "480R-13440=320R+8960<BR>\n" );
document.write( "480R-320R=8960+13440<BR>\n" );
document.write( "160R=22400<BR>\n" );
document.write( "R=22400/160<BR>\n" );
document.write( "R=140 MPH FOR THE PLANE SPEED IN STILL AIR.<BR>\n" );
document.write( "PROOF<BR>\n" );
document.write( "480/(140+28)=480/168=2.8571428 HOURS<BR>\n" );
document.write( "320/(140-28)=320/112=2.8571428 HOURS\r<BR>\n" );
document.write( "\n" );
document.write( "  </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );