document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=682308>Question 682308</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Hi!  I'm helping my stepdaughter with this problem, and we are not sure how to \"set up\" this problem in an equation.  It is stated:\r<BR>\n" );
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document.write( "A freight train leaves a station traveling 60 miles per hour.  Thirty minutes later a passenger train leaves the station in the same direction on a parallel track at a speed of 72 miles per hour.  How long will it take the passenger train to catch the freight train?\r<BR>\n" );
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document.write( "Thank you! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #423122 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=423122\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> First, you need to know how much of<BR>\n" );
document.write( "a head start the freight train got<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+d%5B1%5D+=+60%2A%281%2F2%29+ ALIGN=MIDDLE  ALT=\"+d%5B1%5D+=+60%2A%281%2F2%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%5B1%5D+=+30+ ALIGN=MIDDLE  ALT=\"+d%5B1%5D+=+30+\"   DISABLED_style= \"max-width:90%; height:auto;\" > mi<BR>\n" );
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document.write( "Now start a stopwatch when the passenger <BR>\n" );
document.write( "train leaves the station. Both trains will now<BR>\n" );
document.write( "travel for the same amount of time <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+t+ ALIGN=MIDDLE  ALT=\"+t+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "until they meet.<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;\" > = the distance that the passenger<BR>\n" );
document.write( "train travels until they meet<BR>\n" );
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document.write( "freight train's equation:<BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+d+-+30+=+60t+ ALIGN=MIDDLE  ALT=\"+d+-+30+=+60t+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "passenger train's equation:<BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+d+=+72t+ ALIGN=MIDDLE  ALT=\"+d+=+72t+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "--------------<BR>\n" );
document.write( "Substitute (2) into (1)<BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+72t+-+30+=+60t+ ALIGN=MIDDLE  ALT=\"+72t+-+30+=+60t+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+12t+=+30+ ALIGN=MIDDLE  ALT=\"+12t+=+30+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+t+=+2.5+ ALIGN=MIDDLE  ALT=\"+t+=+2.5+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "The passenger train takes 2.5 hrs to catch the freight train<BR>\n" );
document.write( "check answer:<BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+d+=+72%2A2.5+ ALIGN=MIDDLE  ALT=\"+d+=+72%2A2.5+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+d+=+180+ ALIGN=MIDDLE  ALT=\"+d+=+180+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "and<BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+d+-+30+=+60%2A2.5+ ALIGN=MIDDLE  ALT=\"+d+-+30+=+60%2A2.5+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+d+-+30+=+150+ ALIGN=MIDDLE  ALT=\"+d+-+30+=+150+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+d+=+180+ ALIGN=MIDDLE  ALT=\"+d+=+180+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "OK<BR>\n" );
document.write( "Note that the freight train covers <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+180+-+30+=+150+ ALIGN=MIDDLE  ALT=\"+180+-+30+=+150+\"   DISABLED_style= \"max-width:90%; height:auto;\" > mi<BR>\n" );
document.write( "in the same 2.5 hrs that the passenger train goes <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+180+ ALIGN=MIDDLE  ALT=\"+180+\"   DISABLED_style= \"max-width:90%; height:auto;\" > mi\r<BR>\n" );
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