document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=348379>Question 348379</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A plane that can fly 200 mph in still air makes a 330 mile flight with a tail wind and returns, flying into the same wind. What is the speed of the wind if the total flying time is 3 1/2 hours? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #249060 by </B><A HREF=/tutors/aboutme.mpl?userid=checkley77><B>checkley77(12844)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=checkley77><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=249060\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 3.5=330/(200+20)+330/(200-20)<BR>\n" );
document.write( "3.5=330/220+330/180<BR>\n" );
document.write( "3.5=1.5+1.833<BR>\n" );
document.write( "3.5=3.333 DOESN'T EQUATE TO A PROOF.<BR>\n" );
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document.write( "D=RT<BR>\n" );
document.write( "T=D/R<BR>\n" );
document.write( "3.5=330/(200+W)+330/(200-W)<BR>\n" );
document.write( "3.5=[330(200-W)+330(200+W)]/(200+W)(200-W)<BR>\n" );
document.write( "3.5=[66,000-330W+66,000+330W)/(40,000-W^2)<BR>\n" );
document.write( "3.5=132,000/(40,000-W^2) CROSS MULTIPLY.<BR>\n" );
document.write( "3.5(40,000-W^2)=132,000<BR>\n" );
document.write( "140,000-3.5W^2=132,000<BR>\n" );
document.write( "-3.5W^2=132,000-140,000<BR>\n" );
document.write( "-3.5W^2=-8,000<BR>\n" );
document.write( "W^2=-8,000/-3.5<BR>\n" );
document.write( "W^2=2286<BR>\n" );
document.write( "W=SQRT2286<BR>\n" );
document.write( "W=47.81 MPH FOR THE HEAD WIND.<BR>\n" );
document.write( "PROOF:<BR>\n" );
document.write( "3.5=330/(200+47.81)+330/(200-47.81)<BR>\n" );
document.write( "3.5=330/247.81+330/152.19<BR>\n" );
document.write( "3.5=1.33+2.168<BR>\n" );
document.write( "3.5~3.5<BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );