document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=218146>Question 218146</A>: <I><SPAN STYLE=\"word-break: break-all;\">  Juan rides his bike from Lawrence to Salisbury beach (30 miles in 3 hours).  He divides distance (miles) by time (hours) and sees that his overall average speed is 10mph.  He buys 3 Power bars and eats them.  How fast (mph) must he return so that his overall average speed for the round trip (60 miles) is 15mph?THE ANSWER IS NOT 20mph.<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #164370 by </B><A HREF=/tutors/aboutme.mpl?userid=RAY100><B>RAY100(1637)</B></A><img src=\"/images/stars/stars-12.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=RAY100><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=164370\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Velocity  =  Distance  / Time ,,,,,,or t=d/v<BR>\n" );
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document.write( "outbound,,,,v=30/3 = 10 mph,,,,ok<BR>\n" );
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document.write( "if  total  distance  is  60,,,and  avg  speed  is  to  be 15 mph, t= 60/15 = 4 hrs<BR>\n" );
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document.write( "Since  we  already  used  3  hrs,,,only  one  hr  remains  to  go  30  miles,,,and  v=d/t = 30/1 =30mph<BR>\n" );
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document.write( "Of  course,  neglecting  any  time  spent  at  Salisbury  Beach<BR>\n" );
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