document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=136775>Question 136775</A>: <I><SPAN STYLE=\"word-break: break-all;\"> If a car travels 20 km per hour between two cities. How fast must the car travel to average 40 km per hour for the round trip </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #115317 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=115317\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> If a car travels 20 km per hour between two cities. How fast must the car travel to average 40 km per hour for the round trip<BR>\n" );
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document.write( "It's a trick question, as it's not possible to average 40 kph after going halfway at half that speed.\r<BR>\n" );
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document.write( "If the distance is d, and you travel at speed v, the time is d/20 hours.<BR>\n" );
document.write( "To travel roundtrip, that's 2d.  2d/40 is the same amount of time as d/20, so there is zero (0) time left for the return trip.<BR>\n" );
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