document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=264348>Question 264348</A>: <I><SPAN STYLE=\"word-break: break-all;\"> an airplane flies 450 miles with the wind and 300 against the wind in the same length of time. If the speed of the wind is 40 mph, what is the speed of the airplane 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 #194628 by </B><A HREF=/tutors/aboutme.mpl?userid=Ruli><B>Ruli(21)</B></A><img src=\"/images/stars/stars-07.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Ruli><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=194628\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 450 miles with the wind = 450/(x+40)<BR>\n" );
document.write( "300 against the wind = 300/(x-40)<BR>\n" );
document.write( "450/(x+40) = 300/(x-40)<BR>\n" );
document.write( "multiply each side by (x+40)(x-40) <BR>\n" );
document.write( "450(x-40) = 300(x+40)<BR>\n" );
document.write( "450x - 18,000 = 300x + 12,000<BR>\n" );
document.write( "450x - 18,000 - 300x = 300x + 12,000 - 300x<BR>\n" );
document.write( "150x - 18,000 + 18,000 = 12,000 + 18,000<BR>\n" );
document.write( "150x = 30,000<BR>\n" );
document.write( "divide each side by 150<BR>\n" );
document.write( "x = 200<BR>\n" );
document.write( "The speed of the airplane in still air is 200 mph<BR>\n" );
document.write( "check:<BR>\n" );
document.write( "450/(200+40) = 300/(200-40)<BR>\n" );
document.write( "450/(240) = 300/(160)<BR>\n" );
document.write( "15/8 = 15/8 </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );