document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=149374>Question 149374</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A plane which can fly 100 miles an hour in still air can fly 500 miles with a wind which is blowing at a certain rate in 5/8 of the time it would require to fly 500 miles against a wind blowing at the same rate. What was 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 #109594 by </B><A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><B>ankor@dixie-net.com(22740)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><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=ankor@dixie-net.com><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=109594\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A plane which can fly 100 miles an hour in still air can fly 500 miles with a wind which is blowing at a certain rate in 5/8 of the time it would require to fly 500 miles against a wind blowing at the same rate. What was the rate of the wind?<BR>\n" );
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document.write( "Let x = the rate of the wind<BR>\n" );
document.write( "then<BR>\n" );
document.write( "(100-x) = speed against the wind<BR>\n" );
document.write( "and<BR>\n" );
document.write( "(100+x) = speed with the wind<BR>\n" );
document.write( ":<BR>\n" );
document.write( "Write a time equation: Time = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=dist%2Fspeed ALIGN=MIDDLE  ALT=\"dist%2Fspeed\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
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document.write( "With the wind time = Against time * <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=5%2F8 ALIGN=MIDDLE  ALT=\"5%2F8\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=500%2F%28%28100%2Bx%29%29 ALIGN=MIDDLE  ALT=\"500%2F%28%28100%2Bx%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=500%2F%28%28100-x%29%29 ALIGN=MIDDLE  ALT=\"500%2F%28%28100-x%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > * <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=5%2F8 ALIGN=MIDDLE  ALT=\"5%2F8\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=500%2F%28%28100%2Bx%29%29 ALIGN=MIDDLE  ALT=\"500%2F%28%28100%2Bx%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2500%2F%288%28100-x%29%29 ALIGN=MIDDLE  ALT=\"2500%2F%288%28100-x%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=500%2F%28%28100%2Bx%29%29 ALIGN=MIDDLE  ALT=\"500%2F%28%28100%2Bx%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2500%2F%28%28800-8x%29%29 ALIGN=MIDDLE  ALT=\"2500%2F%28%28800-8x%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Cross multiply:<BR>\n" );
document.write( "2500(100+x) = 500(800-8x)<BR>\n" );
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document.write( "250000 + 2500x = 400000 - 4000x<BR>\n" );
document.write( ";<BR>\n" );
document.write( "2500x + 4000x = 400000 - 250000<BR>\n" );
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document.write( "6500x = 150000<BR>\n" );
document.write( "x = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=150000%2F6500 ALIGN=MIDDLE  ALT=\"150000%2F6500\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "x = 23.1 mph, the rate of the wind<BR>\n" );
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document.write( ":<BR>\n" );
document.write( "Check solution, find the time for each trip<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=500%2F123.1 ALIGN=MIDDLE  ALT=\"500%2F123.1\"   DISABLED_style= \"max-width:90%; height:auto;\" > = 4.06 hrs<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=500%2F76.9 ALIGN=MIDDLE  ALT=\"500%2F76.9\"   DISABLED_style= \"max-width:90%; height:auto;\" > * <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=5%2F8 ALIGN=MIDDLE  ALT=\"5%2F8\"   DISABLED_style= \"max-width:90%; height:auto;\" > = 4.06 hr </SPAN>\n" );
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