document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1025576>Question 1025576</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A train and a car are 180km apart. If they travel towards each other, they will meet in 50 minutes. If they travel in the same direction, the train will overtake the car in 1.8 hours. What is the speed of the train? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #640852 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=640852\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The train can overtake the car only<BR>\n" );
document.write( "if it is faster than the car, so it <BR>\n" );
document.write( "definitely must be faster<BR>\n" );
document.write( "----------------------<BR>\n" );
document.write( "Let <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+s%5Bc%5D+ ALIGN=MIDDLE  ALT=\"+s%5Bc%5D+\"   DISABLED_style= \"max-width:90%; height:auto;\" > = the speed of the car in km/hr<BR>\n" );
document.write( "Let <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+s%5Bt%5D+ ALIGN=MIDDLE  ALT=\"+s%5Bt%5D+\"   DISABLED_style= \"max-width:90%; height:auto;\" > = the speed of the train in km/hr<BR>\n" );
document.write( "------------------------------<BR>\n" );
document.write( "When they travel towards eachother, think of<BR>\n" );
document.write( "one of them standing still and the other <BR>\n" );
document.write( "moving at the sum of their speeds<BR>\n" );
document.write( "------------------------------<BR>\n" );
document.write( "Moving towards eachother:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+180+=+%28+s%5Bt%5D+%2B+s%5Bc%5D+%29%2A%285%2F6%29+ ALIGN=MIDDLE  ALT=\"+180+=+%28+s%5Bt%5D+%2B+s%5Bc%5D+%29%2A%285%2F6%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+s%5Bt%5D+%2B+s%5Bc%5D+=+%286%2F5%29%2A180+ ALIGN=MIDDLE  ALT=\"+s%5Bt%5D+%2B+s%5Bc%5D+=+%286%2F5%29%2A180+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+s%5Bt%5D+%2B+s%5Bc%5D+=+216+ ALIGN=MIDDLE  ALT=\"+s%5Bt%5D+%2B+s%5Bc%5D+=+216+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "------------------------<BR>\n" );
document.write( "When they travel in the same direction, <BR>\n" );
document.write( "subtract the speeds. The car has a <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+180+ ALIGN=MIDDLE  ALT=\"+180+\"   DISABLED_style= \"max-width:90%; height:auto;\" > km<BR>\n" );
document.write( "head start. <BR>\n" );
document.write( "In <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+1.8+ ALIGN=MIDDLE  ALT=\"+1.8+\"   DISABLED_style= \"max-width:90%; height:auto;\" > hrs, the car travels <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+s%5Bc%5D%2A1.8+ ALIGN=MIDDLE  ALT=\"+s%5Bc%5D%2A1.8+\"   DISABLED_style= \"max-width:90%; height:auto;\" > km<BR>\n" );
document.write( "The train travels <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+s%5Bt%5D%2A1.8+ ALIGN=MIDDLE  ALT=\"+s%5Bt%5D%2A1.8+\"   DISABLED_style= \"max-width:90%; height:auto;\" > km<BR>\n" );
document.write( "--------------<BR>\n" );
document.write( "I can say:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+s%5Bt%5D%2A1.8+=+s%5Bc%5D%2A1.8+%2B+180+ ALIGN=MIDDLE  ALT=\"+s%5Bt%5D%2A1.8+=+s%5Bc%5D%2A1.8+%2B+180+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=++s%5Bt%5D%2A1.8+-+s%5Bc%5D%2A1.8+=+180+ ALIGN=MIDDLE  ALT=\"++s%5Bt%5D%2A1.8+-+s%5Bc%5D%2A1.8+=+180+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+1.8%2A%28+s%5Bt%5D+-+s%5Bc%5D+%29+=+180+ ALIGN=MIDDLE  ALT=\"+1.8%2A%28+s%5Bt%5D+-+s%5Bc%5D+%29+=+180+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+s%5Bt%5D+-+s%5Bc%5D+=+100+ ALIGN=MIDDLE  ALT=\"+s%5Bt%5D+-+s%5Bc%5D+=+100+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "---------------------<BR>\n" );
document.write( "Add the equations<BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+s%5Bt%5D+%2B+s%5Bc%5D+=+216+ ALIGN=MIDDLE  ALT=\"+s%5Bt%5D+%2B+s%5Bc%5D+=+216+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+s%5Bt%5D+-+s%5Bc%5D+=+100+ ALIGN=MIDDLE  ALT=\"+s%5Bt%5D+-+s%5Bc%5D+=+100+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "---------------------<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+2s%5Bt%5D+=+316+ ALIGN=MIDDLE  ALT=\"+2s%5Bt%5D+=+316+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+s%5Bt%5D+=+158+ ALIGN=MIDDLE  ALT=\"+s%5Bt%5D+=+158+\"   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=+s%5Bt%5D+%2B+s%5Bc%5D+=+216+ ALIGN=MIDDLE  ALT=\"+s%5Bt%5D+%2B+s%5Bc%5D+=+216+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+158+%2B+s%5Bc%5D+=+216+ ALIGN=MIDDLE  ALT=\"+158+%2B+s%5Bc%5D+=+216+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+s%5Bc%5D+=+58+ ALIGN=MIDDLE  ALT=\"+s%5Bc%5D+=+58+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "-----------------------<BR>\n" );
document.write( "The speed of the train is 158 km/hr<BR>\n" );
document.write( "check:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+180+=+%28+s%5Bt%5D+%2B+s%5Bc%5D+%29%2A%285%2F6%29+ ALIGN=MIDDLE  ALT=\"+180+=+%28+s%5Bt%5D+%2B+s%5Bc%5D+%29%2A%285%2F6%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+180+=+%28+158+%2B+58+%29%2A%285%2F6%29+ ALIGN=MIDDLE  ALT=\"+180+=+%28+158+%2B+58+%29%2A%285%2F6%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+%286%2F5%29%2A180+=+216+ ALIGN=MIDDLE  ALT=\"+%286%2F5%29%2A180+=+216+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+1080+=+5%2A216+ ALIGN=MIDDLE  ALT=\"+1080+=+5%2A216+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+1080+=+1080+ ALIGN=MIDDLE  ALT=\"+1080+=+1080+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "OK </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );