document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=100921>Question 100921</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Max runs the first km of her training session at 8km/h. At least how many kilometers must she run at 15 km/h in order to average 12km/h for the whole session? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #73856 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=73856\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Max runs the first km of her training session at 8km/h. At least how many kilometers must she run at 15 km/h in order to average 12km/h for the whole session<BR>\n" );
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document.write( "Time = distance/speed<BR>\n" );
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document.write( "Let d = distance required at 15 km/h to average 12km/h<BR>\n" );
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document.write( "Write a time equation<BR>\n" );
document.write( "Time at 8 km/h + time at 15 km/h = time at 12/km/h<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1%2F8 ALIGN=MIDDLE  ALT=\"1%2F8\"   DISABLED_style= \"max-width:90%; height:auto;\" > + <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d%2F15 ALIGN=MIDDLE  ALT=\"d%2F15\"   DISABLED_style= \"max-width:90%; height:auto;\" > = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28%28d%2B1%29%29%2F12 ALIGN=MIDDLE  ALT=\"%28%28d%2B1%29%29%2F12\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
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document.write( "Multiply equation by 120 to get rid of the denominators<BR>\n" );
document.write( "120*<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1%2F8 ALIGN=MIDDLE  ALT=\"1%2F8\"   DISABLED_style= \"max-width:90%; height:auto;\" > + 120*<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d%2F15 ALIGN=MIDDLE  ALT=\"d%2F15\"   DISABLED_style= \"max-width:90%; height:auto;\" > = 120*<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28%28d%2B1%29%29%2F12 ALIGN=MIDDLE  ALT=\"%28%28d%2B1%29%29%2F12\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
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document.write( "Cancel out the denominators:<BR>\n" );
document.write( "15(1) + 8(d) = 10(d+1)<BR>\n" );
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document.write( "15 + 8d = 10d + 10<BR>\n" );
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document.write( "8d - 10d = 10 - 15<BR>\n" );
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document.write( "-2d = -5<BR>\n" );
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document.write( "d = + 5/2 or 2.5 km at 15 km/hr rate<BR>\n" );
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document.write( "Total distance would be 3.5 km<BR>\n" );
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document.write( "Check solution by calculating av speed = dist/time<BR>\n" );
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document.write( "Find the time:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1%2F8 ALIGN=MIDDLE  ALT=\"1%2F8\"   DISABLED_style= \"max-width:90%; height:auto;\" > + <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2.5%2F15 ALIGN=MIDDLE  ALT=\"2.5%2F15\"   DISABLED_style= \"max-width:90%; height:auto;\" > =<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1%2F8 ALIGN=MIDDLE  ALT=\"1%2F8\"   DISABLED_style= \"max-width:90%; height:auto;\" > + <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1%2F6 ALIGN=MIDDLE  ALT=\"1%2F6\"   DISABLED_style= \"max-width:90%; height:auto;\" > =<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=3%2F24 ALIGN=MIDDLE  ALT=\"3%2F24\"   DISABLED_style= \"max-width:90%; height:auto;\" >+ <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=4%2F24 ALIGN=MIDDLE  ALT=\"4%2F24\"   DISABLED_style= \"max-width:90%; height:auto;\" > = 7/24 hr, is the total time<BR>\n" );
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document.write( "Check average speed (dist/time)<BR>\n" );
document.write( "7/2 (3.5) divided by 7/24<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=7%2F2 ALIGN=MIDDLE  ALT=\"7%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" > * <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=24%2F7 ALIGN=MIDDLE  ALT=\"24%2F7\"   DISABLED_style= \"max-width:90%; height:auto;\" > = 24/2 = 12 km/hr\r<BR>\n" );
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document.write( "Sorry, I got twisted around on the first attempt </SPAN>\n" );
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