document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=213740>Question 213740</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A bus driver leaves the station at 10am at 40mph. He forgets to pack luggage underneath the bus and a car is dispatched 1hr later with the forgotten luggage. If the car has only 2hrs to catch up the bus, how fast does the car need to drive? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #161465 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=161465\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> If the car drives 40 mi/hr or less, it can  never<BR>\n" );
document.write( "catch the bus.<BR>\n" );
document.write( "The car leaves 1 hr after the bus has left<BR>\n" );
document.write( "In 1 hr, the bus has gone <BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d+=40%2A1 ALIGN=MIDDLE  ALT=\"d+=40%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+=+40 ALIGN=MIDDLE  ALT=\"d+=+40\"   DISABLED_style= \"max-width:90%; height:auto;\" > mi<BR>\n" );
document.write( "I have a stopwatch which I will start when the car leaves<BR>\n" );
document.write( "and I'll stop it when the car catches the bus.<BR>\n" );
document.write( "Both vehicles will drive for 2 hrs, but the bus has<BR>\n" );
document.write( "a <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=40 ALIGN=MIDDLE  ALT=\"40\"   DISABLED_style= \"max-width:90%; height:auto;\" > mi headstart.<BR>\n" );
document.write( "Let <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d ALIGN=MIDDLE  ALT=\"d\"   DISABLED_style= \"max-width:90%; height:auto;\" > = distance the car goes in 2 hrs<BR>\n" );
document.write( "Let <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=r ALIGN=MIDDLE  ALT=\"r\"   DISABLED_style= \"max-width:90%; height:auto;\" > = speed of the car in mi/hr<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d+-+40 ALIGN=MIDDLE  ALT=\"d+-+40\"   DISABLED_style= \"max-width:90%; height:auto;\" > = distance the bus travels<BR>\n" );
document.write( "Let <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t+=+2 ALIGN=MIDDLE  ALT=\"t+=+2\"   DISABLED_style= \"max-width:90%; height:auto;\" > hrs for both<BR>\n" );
document.write( "For car:<BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d+=+r%2A2 ALIGN=MIDDLE  ALT=\"d+=+r%2A2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "For bus:<BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d+-+40+=+40%2A2 ALIGN=MIDDLE  ALT=\"d+-+40+=+40%2A2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Substitute (1) in (2)<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2r+-+40+=+80 ALIGN=MIDDLE  ALT=\"2r+-+40+=+80\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2r+=+120 ALIGN=MIDDLE  ALT=\"2r+=+120\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=r+=+60 ALIGN=MIDDLE  ALT=\"r+=+60\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "The car needs to go 60 mi/hr to catch the bus in 2 hrs<BR>\n" );
document.write( "check answer<BR>\n" );
document.write( "In 2 hrs, the bus goes<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d+=+40%2A2 ALIGN=MIDDLE  ALT=\"d+=+40%2A2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d+=+80+mi ALIGN=MIDDLE  ALT=\"d+=+80+mi\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=80+%2B+40+=+120 ALIGN=MIDDLE  ALT=\"80+%2B+40+=+120\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "The car needs to go a total of 120 mi in 2 hrs<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;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=120+=+r%2A2 ALIGN=MIDDLE  ALT=\"120+=+r%2A2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=r+=+60 ALIGN=MIDDLE  ALT=\"r+=+60\"   DISABLED_style= \"max-width:90%; height:auto;\" > mi/hr<BR>\n" );
document.write( "OK\r<BR>\n" );
document.write( "\n" );
document.write( "    </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );