document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=307439>Question 307439</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A jet plane flying with the wind flew 2400 miles in 4 hours. Against the wind, the plane flew only 2000 miles in 4 hours. Find the rate of the plane in calm air and the rate of the wind. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #219948 by </B><A HREF=/tutors/aboutme.mpl?userid=rapaljer><B>rapaljer(4671)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=rapaljer><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=rapaljer><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=219948\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Let x = rate of the plane in still air.<BR>\n" );
document.write( "Let y = rate of the wind.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=Rate+=+%28Distance%29%2F%28Time%29 ALIGN=MIDDLE  ALT=\"Rate+=+%28Distance%29%2F%28Time%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Rate WITH the wind = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%2By=2400%2F4 ALIGN=MIDDLE  ALT=\"x%2By=2400%2F4\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Rate AGAINST the wind = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x-y=2000%2F4 ALIGN=MIDDLE  ALT=\"x-y=2000%2F4\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "x+y=600<BR>\n" );
document.write( "x-y=500\r<BR>\n" );
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document.write( "Add the equations together:<BR>\n" );
document.write( "2x=1100<BR>\n" );
document.write( "x=550 mph = speed of the plane in still air.\r<BR>\n" );
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document.write( "Now, x+y=600, where x=550<BR>\n" );
document.write( "550+y=600<BR>\n" );
document.write( "y=50 mph = speed of the wind.\r<BR>\n" );
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document.write( "Dr. Robert J. Rapalje, Retired<BR>\n" );
document.write( "Seminole State College of Florida </SPAN>\n" );
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