document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1043838>Question 1043838</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I need help with this question:\r<BR>\n" );
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document.write( "a plane flies 440 miles with the wind and 330 in the same length of time If the speed of the wind is 21.  what is the speed of the plane in still&#8203; air? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #659002 by </B><A HREF=/tutors/aboutme.mpl?userid=Boreal><B>Boreal(15235)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Boreal><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=Boreal><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=659002\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> I'm assuming the plane's speed x allows it to travel 440 miles with the wind and in the same time 330 miles against the wind.<BR>\n" );
document.write( "(x+21)t=440, t=440/(x+21); rate x time =distance. time=distance/rate<BR>\n" );
document.write( "(x-21)t=330, t=330/(x-21)<BR>\n" );
document.write( "Set the two values equal to each other.<BR>\n" );
document.write( "440/(x+21)=330/(x-21)<BR>\n" );
document.write( "cross multiply<BR>\n" );
document.write( "440x-9240=330x+6930<BR>\n" );
document.write( "110x=16170<BR>\n" );
document.write( "x=147 mph ANSWER<BR>\n" );
document.write( "with the wind, 168 mph and 440/168=2.619 hours<BR>\n" );
document.write( "against the wind, 126 mph and 330/126=2.619 hours, checks. </SPAN>\n" );
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