document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=10257>Question 10257</A>: <I><SPAN STYLE=\"word-break: break-all;\"> My math problem is this:<BR>\n" );
document.write( "A car goes from point A to point B, at a rate of 40 mph. Then the same car turns around and goes from point B to point A, at a rate of 60 mph. What is the average speen of this car? My teacher said that it was not 50 mph. I am very confused on this and would like a thurough explination. Thank you so much for this. :D I need all the help, and it is very much appreciated. I've spent time trying to figure out the answer to this, and I've come up with an average speed of 55 mph, but I am not sure how I got that, and I don't know how to check if it is right. Please help me and thank you.  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #5509 by </B><A HREF=/tutors/aboutme.mpl?userid=gsmani_iyer><B>gsmani_iyer(201)</B></A><img src=\"/images/stars/stars-09.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=gsmani_iyer><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=gsmani_iyer><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=5509\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <BR>\n" );
document.write( "  Let us say the distance between A and B = 120 miles.   (Why 120?)\r<BR>\n" );
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document.write( "  So while going from A to B @ 40mph,<BR>\n" );
document.write( "  the time taken  is = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=120%2F40 ALIGN=MIDDLE  ALT=\"120%2F40\"   DISABLED_style= \"max-width:90%; height:auto;\" > = 3 hrs.\r<BR>\n" );
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document.write( "  While coming from B to A @ 60mph<BR>\n" );
document.write( "  the time taken is = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=120%2F60 ALIGN=MIDDLE  ALT=\"120%2F60\"   DISABLED_style= \"max-width:90%; height:auto;\" > = 2 hrs.\r<BR>\n" );
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document.write( "  Total distance travelled = 240 miles <BR>\n" );
document.write( "  Total time taken to cover= 3+2 = 5 hrs.\r<BR>\n" );
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document.write( "  So the average speed = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=240%2F5 ALIGN=MIDDLE  ALT=\"240%2F5\"   DISABLED_style= \"max-width:90%; height:auto;\" > = 48 mph.  Answer\r<BR>\n" );
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document.write( "  why I have taken 120 is because 120 is the LCM of both 40 and 60 and <BR>\n" );
document.write( "  120 is divisible by both 40 and 60.  It is the only reason. Then it will <BR>\n" );
document.write( "  be easy to solve the problem.<BR>\n" );
document.write( "  I hope you understood this. \r<BR>\n" );
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document.write( "  gsm\r<BR>\n" );
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document.write( " </SPAN>\n" );
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