document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=279459>Question 279459</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A cross country skier walks 3000m up a mountain road, rests for 10 minutes and then skis down the road. he returns a half hour after he started. if he skis four times as fast as he walks, at what rate does he ski?\r<BR>\n" );
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document.write( "( having a hard time grasping these word problems and what dictates a constant factor and how to build the equation. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #203204 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=203204\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A cross country skier walks 3000m up a mountain road, rests for 10 minutes<BR>\n" );
document.write( " and then skis down the road.<BR>\n" );
document.write( " he returns a half hour after he started. if he skis four times as fast as<BR>\n" );
document.write( " he walks, at what rate does he ski?<BR>\n" );
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document.write( "Change half hour to 30 min <BR>\n" );
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document.write( "Let w = his walking speed (in meters/minute)<BR>\n" );
document.write( "then<BR>\n" );
document.write( "4w = his skiing speed<BR>\n" );
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document.write( "Write a time equation: time = dist/speed<BR>\n" );
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document.write( "up time + 10 min + down time = 30 min<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=3000%2Fw ALIGN=MIDDLE  ALT=\"3000%2Fw\"   DISABLED_style= \"max-width:90%; height:auto;\" > + 10 + <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=3000%2F%284w%29 ALIGN=MIDDLE  ALT=\"3000%2F%284w%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > = 30<BR>\n" );
document.write( "Multiply by 4W,results<BR>\n" );
document.write( "4(3000) + 4w(10) + 3000 = 4w(30)<BR>\n" );
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document.write( "12000 + 40w + 3000 = 120w<BR>\n" );
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document.write( "12000 + 3000 = 120w - 40w<BR>\n" );
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document.write( "15000 = 80w<BR>\n" );
document.write( "w = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=15000%2F80 ALIGN=MIDDLE  ALT=\"15000%2F80\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "w = 187.5 m/min; his walking speed<BR>\n" );
document.write( "and<BR>\n" );
document.write( "4(187.5) = 750 m/min is his skiing speed<BR>\n" );
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document.write( "That would be: <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28750%2A60%29%2F1000 ALIGN=MIDDLE  ALT=\"%28750%2A60%29%2F1000\"   DISABLED_style= \"max-width:90%; height:auto;\" > = 45 km/hr<BR>\n" );
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document.write( "Check solution by finding the times<BR>\n" );
document.write( "3000/187.5 = 16 min<BR>\n" );
document.write( "resting time:10 min<BR>\n" );
document.write( "3000/750.0 =  4 min<BR>\n" );
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document.write( "total time = 30 min; confirms our solution </SPAN>\n" );
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