document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=136760>Question 136760</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A train M leaves station A at 5 a.m. and reaches station B at 9 a.m. Another train N leaves station B at 7 a.m and reaches station A at 10.30 a.m. At what time do the two trains cross one another? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #100123 by </B><A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><B>ankor@dixie-net.com(22740)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><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=ankor@dixie-net.com><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=100123\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A train M leaves station A at 5 a.m. and reaches station B at 9 a.m. Another train N leaves station B at 7 a.m and reaches station A at 10.30 a.m. At what time do the two trains cross one another?<BR>\n" );
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document.write( "From the information given, we can say:<BR>\n" );
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document.write( "M takes 4 hrs to go from A to B<BR>\n" );
document.write( "and<BR>\n" );
document.write( "N takes 3.5 hrs to from B to A<BR>\n" );
document.write( "also<BR>\n" );
document.write( "Train N leaves B, 2 hrs after M leaves A<BR>\n" );
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document.write( "It will easier if we choose a distance value for A to B<BR>\n" );
document.write( "I chose 280 mi, both 4 and 3.5 will divide into it evenly<BR>\n" );
document.write( "Find the speed of both trains from this<BR>\n" );
document.write( "280/4 = 70 mph speed of M<BR>\n" );
document.write( "280/3.5 = 80 mph speed of N<BR>\n" );
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document.write( "When they cross the total distance traveled by both trains = 280 mi<BR>\n" );
document.write( "Let t = time (hrs) of train M<BR>\n" );
document.write( "then<BR>\n" );
document.write( "(t-2) = time of train N<BR>\n" );
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document.write( "Dist = speed * time<BR>\n" );
document.write( "70t + 80(t-2) = 280<BR>\n" );
document.write( "70t + 180t - 160 = 280<BR>\n" );
document.write( "150t = 280 + 160<BR>\n" );
document.write( "t = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=440%2F150 ALIGN=MIDDLE  ALT=\"440%2F150\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "t = 2<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=140%2F150 ALIGN=MIDDLE  ALT=\"140%2F150\"   DISABLED_style= \"max-width:90%; height:auto;\" > = 2<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=14%2F15 ALIGN=MIDDLE  ALT=\"14%2F15\"   DISABLED_style= \"max-width:90%; height:auto;\" > hrs travel time of M when the cross<BR>\n" );
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document.write( "Change 14/15 hrs to min: 14/15 * 60 = 56 min<BR>\n" );
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document.write( "2 hr 56 min from 5 am = 7:56 am time when they cross.<BR>\n" );
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document.write( "Check solution (train N travel time will be 56 min or 14/15 hr<BR>\n" );
document.write( "N dist: 14/15 * 80 = 74.67 mi<BR>\n" );
document.write( "M dist: 44/15 * 70 =205.33 mi<BR>\n" );
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document.write( "Train dist totals: =280 mi \r<BR>\n" );
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document.write( " </SPAN>\n" );
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