document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=46652>Question 46652</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Show a complete solution to each problem.<BR>\n" );
document.write( "Big Plane. A six passenger plane cruises at 180 mph in calm air. If the plane flies 7 miles with the wind in the same amount of time as it flies 5 miles against the wind then what is the wind speed?\r<BR>\n" );
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document.write( "Thanks<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #30897 by </B><A HREF=/tutors/aboutme.mpl?userid=adamchapman><B>adamchapman(301)</B></A><img src=\"/images/stars/stars-10.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=adamchapman><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=30897\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Finally, a question about aeroplanes!\r<BR>\n" );
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document.write( "Let the windspeed be called \"w\" and the time taken be called \"t\".<BR>\n" );
document.write( "We know that the time taken for the plane to cover a certain distance is equal to its speed divided by that distance.<BR>\n" );
document.write( "We can now write two equations:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28180%2Bw%29%2F7=t ALIGN=MIDDLE  ALT=\"%28180%2Bw%29%2F7=t\"   DISABLED_style= \"max-width:90%; height:auto;\" > (with the wind)<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28180-w%29%2F5=t ALIGN=MIDDLE  ALT=\"%28180-w%29%2F5=t\"   DISABLED_style= \"max-width:90%; height:auto;\" > (against the wind)<BR>\n" );
document.write( "Notice how both equations are equal to \"t\". This means we can say:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28180%2Bw%29%2F7=%28180-w%29%2F5 ALIGN=MIDDLE  ALT=\"%28180%2Bw%29%2F7=%28180-w%29%2F5\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Now rearrange to find \"w\":<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=5%28180%2Bw%29=7%28180-w%29 ALIGN=MIDDLE  ALT=\"5%28180%2Bw%29=7%28180-w%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=900%2B5w=1260-7w ALIGN=MIDDLE  ALT=\"900%2B5w=1260-7w\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=12w=360 ALIGN=MIDDLE  ALT=\"12w=360\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=w=360%2F12=30 ALIGN=MIDDLE  ALT=\"w=360%2F12=30\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "So the wind speed is 30mph.<BR>\n" );
document.write( "I hope this helps,<BR>\n" );
document.write( "Adam.<BR>\n" );
document.write( "P.S. please visit mt website, it might be useful to you. The address is http://www.geocities.com/quibowibbler\r<BR>\n" );
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