document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=32609>Question 32609</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A train leaves a station and travels east at 72 km/h. Three hours later a second train leaves on a parrallel track and travels east at 120 km/h. When will it overtake the first train? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #19110 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=19110\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> It usually helps to make a chart for these problems<BR>\n" );
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document.write( "...............distance travelled.....|.rate km/hr.|..time hrs<BR>\n" );
document.write( "-----------------------------------------------------------------------<BR>\n" );
document.write( "slow train........72t....................|.........72..........|......t<BR>\n" );
document.write( "-----------------------------------------------------------------------<BR>\n" );
document.write( "fast train........120(t - 3).........|........120..........|......t - 3<BR>\n" );
document.write( "-----------------------------------------------------------------------\r<BR>\n" );
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document.write( "The time the fast train is running is 3 hours less than the slow one,<BR>\n" );
document.write( "but the distance it travels is the same as the fast one. That's where<BR>\n" );
document.write( "they meet. So set the distances in the chart equal to eachother.\r<BR>\n" );
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document.write( "72t = 120(t - 3)<BR>\n" );
document.write( "72t = 120t - 360<BR>\n" );
document.write( "subtract 72t from each side<BR>\n" );
document.write( "48t = 360<BR>\n" );
document.write( "t = 7.5<BR>\n" );
document.write( "This is the time it takes the slow train to get to where they meet, <BR>\n" );
document.write( "but the  problem wants ti know weh the fast train will overtake it<BR>\n" );
document.write( "It will take the fast train (t - 3) hours to overtake the slow one.<BR>\n" );
document.write( "t = 7.5<BR>\n" );
document.write( "(t - 3) = (7.5 - 3) = 4.5 hours<BR>\n" );
document.write( "check the answer<BR>\n" );
document.write( "72t = 120(t - 3)<BR>\n" );
document.write( "72(7.5) = 120(7.5 - 3)<BR>\n" );
document.write( "540 = 120*4.5<BR>\n" );
document.write( "540 = 540<BR>\n" );
document.write( "OK </SPAN>\n" );
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