document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=450568>Question 450568</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Could you please help me on how to solve this problem; I tried to figure out the answer but it do not look right.\r<BR>\n" );
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document.write( "\"John found his plane could fly at 6 times the speed of the wind. He flew 700 miles upwind in 3 hours more than it took to fly 560 miles downwind. What was the speed of the plan in still air?\"\r<BR>\n" );
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document.write( "My answer:  (a). (A + W)T_D = D_D<BR>\n" );
document.write( "    (b). (A – W)T_U = D_U\r<BR>\n" );
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document.write( "(6W + W)(T_U + 3) = 560       &#8594;    <BR>\n" );
document.write( "(6W + W)T_U = 700<BR>\n" );
document.write( "7WT_U + 3W = 560              &#8594;   <BR>\n" );
document.write( "7WT_U = 700  &#8594;   <BR>\n" );
document.write( "WT_U  = 100<BR>\n" );
document.write( "7(100) + 3W = 560  &#8594;   \r<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 #309895 by </B><A HREF=/tutors/aboutme.mpl?userid=rwm><B>rwm(914)</B></A><img src=\"/images/stars/stars-11.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=rwm><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=309895\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> John found his plane could fly at 6 times the speed of the wind. He flew 700 miles upwind in 3 hours more than it took to fly 560 miles downwind. What was the speed of the plan in still air?\"<BR>\n" );
document.write( "upwind=against the wind<BR>\n" );
document.write( "let <BR>\n" );
document.write( "wind=w<BR>\n" );
document.write( "downwind=+w<BR>\n" );
document.write( "upwind=-w\r<BR>\n" );
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document.write( "p=plane<BR>\n" );
document.write( "p=6w<BR>\n" );
document.write( "r*t=d<BR>\n" );
document.write( "(p-w)(3+t)=700<BR>\n" );
document.write( "(p+w)t=560<BR>\n" );
document.write( "(6w-w)(3+t)=700<BR>\n" );
document.write( "(6w+w)t=560\r<BR>\n" );
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document.write( "(5w)(3+t)=700<BR>\n" );
document.write( "w*(3+t)=140\r<BR>\n" );
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document.write( "(7w)t=560<BR>\n" );
document.write( "wt=80<BR>\n" );
document.write( "w=80/t<BR>\n" );
document.write( "w=140/(3+t)<BR>\n" );
document.write( "80/t=140/(3+t)<BR>\n" );
document.write( "4/t=7/(3+t)<BR>\n" );
document.write( "4*(3+t)=7t<BR>\n" );
document.write( "12+4t=7t<BR>\n" );
document.write( "12=3t<BR>\n" );
document.write( "4=t<BR>\n" );
document.write( "wt=80<BR>\n" );
document.write( "w=20<BR>\n" );
document.write( "p=6*w=120 in still air\r<BR>\n" );
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document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );