document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=173418>Question 173418</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A six-passenger plane cruises at 180 mph in<BR>\n" );
document.write( "calm air. If the plane flies 7 miles with the wind in the<BR>\n" );
document.write( "same amount of time as it flies 5 miles against the wind,<BR>\n" );
document.write( "then what is the wind speed?\r<BR>\n" );
document.write( "\n" );
document.write( "I have no idea how to start this question.  I tried D=RT but i got no where </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #128269 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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=128269\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A six-passenger plane cruises at 180 mph in<BR>\n" );
document.write( "calm air. If the plane flies 7 miles with the wind in the<BR>\n" );
document.write( "same amount of time as it flies 5 miles against the wind,<BR>\n" );
document.write( "then what is the wind speed? <BR>\n" );
document.write( "--------------------------------------------<BR>\n" );
document.write( "Yes, use d= rt<BR>\n" );
document.write( "------------------<BR>\n" );
document.write( "With-wind DATA:<BR>\n" );
document.write( "distance = 7 miles; rate = 180+wind ; time = d/r = 7/(180+w) hrs<BR>\n" );
document.write( "--------------<BR>\n" );
document.write( "Against-wind DATA:<BR>\n" );
document.write( "distance = 5 miles ; rate = 180-w ; time = d/r = 5/(180-w) hrs<BR>\n" );
document.write( "-------------<BR>\n" );
document.write( "time = time<BR>\n" );
document.write( "7/(180+w) = 5/(180-w)\r<BR>\n" );
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document.write( "7(180-w) = 5(180+w)<BR>\n" );
document.write( "7*180 - 7w= 5*180 + 5w<BR>\n" );
document.write( "12w = 2*180<BR>\n" );
document.write( "w = 2*15<BR>\n" );
document.write( "wind speed = 30 mph<BR>\n" );
document.write( "=======================<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );