document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=171435>Question 171435</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Having trouble finding the right formula! How do I solve?\r<BR>\n" );
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document.write( "An express and local train leave Gray's Lake at 3 P.M. and head for Chicago 50 miles away. The express travels twice as fast as the local, and arrives 1 hour ahead of it. Find the speed of each train.<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 #126567 by </B><A HREF=/tutors/aboutme.mpl?userid=Mathtut><B>Mathtut(3670)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Mathtut><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=126567\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> d=rt.   we know the distance in both cases is 50. Lets call the local trains rate r and its time t.  So the express's rate would be 2r and its time t-1<BR>\n" );
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document.write( "50=rt..........eq 1<BR>\n" );
document.write( "50=2r(t-1).....eq 2<BR>\n" );
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document.write( "lets rewrite eq 1 as t=50/r and plug that value into eq 2<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=50=2r%28%2850%2Fr%29-1%29 ALIGN=MIDDLE  ALT=\"50=2r%28%2850%2Fr%29-1%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >-----><IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=50=2r%28%2850-r%29%2Fr%29 ALIGN=MIDDLE  ALT=\"50=2r%28%2850-r%29%2Fr%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >----<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=50=2cross%28r%29%2850-r%29%2Fcross%28r%29 ALIGN=MIDDLE  ALT=\"50=2cross%28r%29%2850-r%29%2Fcross%28r%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=50=100-2r ALIGN=MIDDLE  ALT=\"50=100-2r\"   DISABLED_style= \"max-width:90%; height:auto;\" >----><IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-2r=-50 ALIGN=MIDDLE  ALT=\"-2r=-50\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight%28r=25%29 ALIGN=MIDDLE  ALT=\"highlight%28r=25%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >MPH-speed of the local train<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight%282%2825%29=50%29 ALIGN=MIDDLE  ALT=\"highlight%282%2825%29=50%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >MPH-speed of the express<BR>\n" );
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