document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1203160>Question 1203160</A>: <I><SPAN STYLE=\"word-break: break-all;\"> How do I go about setting up this equation?\r<BR>\n" );
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document.write( "2 trains are a mile and a 1/2 apart\r<BR>\n" );
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document.write( "A is traveling at 3/4ths the speed of train B\r<BR>\n" );
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document.write( "they'll collide in 4 1/2 minutes\r<BR>\n" );
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document.write( "how fast is each train going\r<BR>\n" );
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document.write( "Thanks in advance. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #838502 by </B><A HREF=/tutors/aboutme.mpl?userid=Alan3354><B>Alan3354(69443)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Alan3354><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=Alan3354><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=838502\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> How do I go about setting up this equation?\r<BR>\n" );
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document.write( "2 trains are a mile and a 1/2 apart\r<BR>\n" );
document.write( "\n" );
document.write( "A is traveling at 3/4ths the speed of train B\r<BR>\n" );
document.write( "\n" );
document.write( "they'll collide in 4 1/2 minutes\r<BR>\n" );
document.write( "\n" );
document.write( "how fast is each train going<BR>\n" );
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document.write( "The fact that they'll collide implies they're moving toward each other, so the speeds are added.<BR>\n" );
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document.write( "A = 0.75B<BR>\n" );
document.write( "A + B = 1.75B (the \"closing speed\")<BR>\n" );
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document.write( "d = r*t<BR>\n" );
document.write( "1.5 = 1.75B*4.5<BR>\n" );
document.write( "B = 1.5/(1.75*4.5) = 1/5.25 miles/minute<BR>\n" );
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document.write( "A = 0.75B = 1/7 miles/minute<BR>\n" );
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document.write( "Multiply by 60 to get miles per hour<BR>\n" );
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