document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=874286>Question 874286</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Given: d = rt, where \"d\" is distance, \"r\" is rate, and \"t\" is time.<BR>\n" );
document.write( "    Two trains on the same track, initially 648 miles apart, leave from <BR>\n" );
document.write( "    their positions simultaneously. They are on a head-on collision <BR>\n" );
document.write( "    course. One train is traveling 35 mi/hr and the other is traveling<BR>\n" );
document.write( "    85 mi/hr.  What is the length of time to impact?<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #527426 by </B><A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><B>josgarithmetic(39620)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=527426\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> More generally, two trains initially m miles apart start traveling toward each other simultaneously.  One is going r mph and the other s mph.  How much time to meet?\r<BR>\n" );
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document.write( "The unknown variable is t, in:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=rt%2Bst=m ALIGN=MIDDLE  ALT=\"rt%2Bst=m\"   DISABLED_style= \"max-width:90%; height:auto;\" >, because the sum of their distances traveled will be m when they meet, or collide.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t%28r%2Bs%29=m ALIGN=MIDDLE  ALT=\"t%28r%2Bs%29=m\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight%28t=m%2F%28r%2Bs%29%29 ALIGN=MIDDLE  ALT=\"highlight%28t=m%2F%28r%2Bs%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >.<BR>\n" );
document.write( "Substitute the values to find that of t. </SPAN>\n" );
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