document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=547710>Question 547710</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A person travels 136 miles from one town to a city at an average speed of 77 mph and then returns home at an average speed of 56 mph. <BR>\n" );
document.write( "What was the average speed over the total distance covered? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #356526 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=356526\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A person travels 136 miles from one town to a city at an average speed of 77 mph and then returns home at an average speed of 56 mph. <BR>\n" );
document.write( "What was the average speed over the total distance covered?<BR>\n" );
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document.write( "Avg speed of a round trip is 2*R1*R2/(R1 + R2) R1 & R2 are the 2 rates.  <BR>\n" );
document.write( "I worked this out some time ago while looking at the Michelson-Morley experiment.<BR>\n" );
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document.write( "It's similar to parallel resistors and parallel flows, but with a factor of 2.<BR>\n" );
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document.write( "Avg speed of the round trip = 2*77*56/(77+56)<BR>\n" );
document.write( "=~ 64.84 mi/hr\r<BR>\n" );
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