document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=102404>Question 102404</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Mary and Jocelyn are sisters.  They left the school at 3:00 P.M. and bicycled home along the same bike path.  Mary bicycled at a speed of 12 mi/h.  Jocelyn bicycled at 9 mi/h.  Mary got home 15 min. before Jocelyn.  How long did it take Mary to get home?<BR>\n" );
document.write( "Define a variable(s), set up and solve. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #74493 by </B><A HREF=/tutors/aboutme.mpl?userid=josmiceli><B>josmiceli(19441)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=josmiceli><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=josmiceli><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=74493\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> In these kind of problems, bikes, trains, boats, etc. it <BR>\n" );
document.write( "really helps if the first question you ask is \"what is the<BR>\n" );
document.write( "same for both?\" In this case it's the distance from school to home,<BR>\n" );
document.write( "and also, they both start at 3 PM.<BR>\n" );
document.write( "Notice everything else is different.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d+=+r%2At ALIGN=MIDDLE  ALT=\"d+=+r%2At\"   DISABLED_style= \"max-width:90%; height:auto;\" > holds true for both<BR>\n" );
document.write( "For Mary,<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t%5BM%5D+=+t%5BJ%5D+-+15 ALIGN=MIDDLE  ALT=\"t%5BM%5D+=+t%5BJ%5D+-+15\"   DISABLED_style= \"max-width:90%; height:auto;\" > in minutes<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=r%5BM%5D+=+12 ALIGN=MIDDLE  ALT=\"r%5BM%5D+=+12\"   DISABLED_style= \"max-width:90%; height:auto;\" > in mi/hr<BR>\n" );
document.write( "For Jocelyn, <BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=r%5BJ%5D+=+9 ALIGN=MIDDLE  ALT=\"r%5BJ%5D+=+9\"   DISABLED_style= \"max-width:90%; height:auto;\" > in mi/hr<BR>\n" );
document.write( "Now write equations<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d%5BM%5D+=+d%5BJ%5D ALIGN=MIDDLE  ALT=\"d%5BM%5D+=+d%5BJ%5D\"   DISABLED_style= \"max-width:90%; height:auto;\" > because they're going the same distance, so call<BR>\n" );
document.write( "them both <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d ALIGN=MIDDLE  ALT=\"d\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d+=+r%5BM%5D%2At%5BM%5D ALIGN=MIDDLE  ALT=\"d+=+r%5BM%5D%2At%5BM%5D\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d+=+r%5BM%5D%2A%28t%5BJ%5D+-+.25%29 ALIGN=MIDDLE  ALT=\"d+=+r%5BM%5D%2A%28t%5BJ%5D+-+.25%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > (Note I converted 15 minutes to .25 hrs)<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d+=+12%2A%28t%5BJ%5D+-+.25%29 ALIGN=MIDDLE  ALT=\"d+=+12%2A%28t%5BJ%5D+-+.25%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Now for Jocelyn,<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d+=+r%5BJ%5D%2At%5BJ%5D ALIGN=MIDDLE  ALT=\"d+=+r%5BJ%5D%2At%5BJ%5D\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d+=+9%2At%5BJ%5D ALIGN=MIDDLE  ALT=\"d+=+9%2At%5BJ%5D\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Now set the equations equal to eachother<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=12%2A%28t%5BJ%5D+-+.25%29+=+9%2At%5BJ%5D ALIGN=MIDDLE  ALT=\"12%2A%28t%5BJ%5D+-+.25%29+=+9%2At%5BJ%5D\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=12%2At%5BJ%5D+-+3+=+9%2At%5BJ%5D ALIGN=MIDDLE  ALT=\"12%2At%5BJ%5D+-+3+=+9%2At%5BJ%5D\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=3%2At%5BJ%5D+=+3 ALIGN=MIDDLE  ALT=\"3%2At%5BJ%5D+=+3\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t%5BJ%5D+=+1 ALIGN=MIDDLE  ALT=\"t%5BJ%5D+=+1\"   DISABLED_style= \"max-width:90%; height:auto;\" > in hours<BR>\n" );
document.write( "Mary got home a quarter hour before Jocelyn, so<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t%5BM%5D+=+.75 ALIGN=MIDDLE  ALT=\"t%5BM%5D+=+.75\"   DISABLED_style= \"max-width:90%; height:auto;\" > in hours<BR>\n" );
document.write( "Or, Mary's time was 45 minutes<BR>\n" );
document.write( "You should chck these answers by putting them back in the<BR>\n" );
document.write( "original equations<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d+=+12%2A%28t%5BJ%5D+-+.25%29 ALIGN=MIDDLE  ALT=\"d+=+12%2A%28t%5BJ%5D+-+.25%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d+=+12%2A%281+-+.25%29 ALIGN=MIDDLE  ALT=\"d+=+12%2A%281+-+.25%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d+=+12%2A%283%2F4%29 ALIGN=MIDDLE  ALT=\"d+=+12%2A%283%2F4%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d+=+9 ALIGN=MIDDLE  ALT=\"d+=+9\"   DISABLED_style= \"max-width:90%; height:auto;\" > in miles<BR>\n" );
document.write( "and<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d+=+9%2At%5BJ%5D ALIGN=MIDDLE  ALT=\"d+=+9%2At%5BJ%5D\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d+=+9%2A1 ALIGN=MIDDLE  ALT=\"d+=+9%2A1\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d+=+9 ALIGN=MIDDLE  ALT=\"d+=+9\"   DISABLED_style= \"max-width:90%; height:auto;\" > in miles<BR>\n" );
document.write( "So, you get the same answer for school - home distance </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );