document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=830352>Question 830352</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Please could you help me with this question: <BR>\n" );
document.write( "\"Sarah goes up a hill and then down again the same way.On the way up she averages 2 miles per hour. On the way down she averages 4 miles per hour. What is Sarah's average speed in miles per hour for the whole journey?\"<BR>\n" );
document.write( "I know that the answer is 2.6 miles per hour but I'm not sure how to work it out.<BR>\n" );
document.write( "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 #500537 by </B><A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><B>josgarithmetic(39617)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><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=500537\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> x time up<BR>\n" );
document.write( "y time down<BR>\n" );
document.write( "d one-way distance up or down\r<BR>\n" );
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document.write( "________________speed___________time________________distance<BR>\n" );
document.write( "up hill_________2________________x__________________d<BR>\n" );
document.write( "down hill_______4________________y__________________d<BR>\n" );
document.write( "Total?________________________x+y__________________2d\r<BR>\n" );
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document.write( "The relationship of speeds means you can make a relationship of the times.\r<BR>\n" );
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document.write( "Twice as fast down the hill means HALF the time as up the hill:\r<BR>\n" );
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document.write( "________________speed___________time________________distance<BR>\n" );
document.write( "up hill_________2________________x__________________d<BR>\n" );
document.write( "down hill_______4________________x/2__________________d<BR>\n" );
document.write( "Total?________________________(3/2)x__________________2d\r<BR>\n" );
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document.write( "Can we find expressions for d?\r<BR>\n" );
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document.write( "________________speed___________time________________distance<BR>\n" );
document.write( "up hill_________2________________x__________________d=2x<BR>\n" );
document.write( "down hill_______4________________x/2__________________d=4(x/2)<BR>\n" );
document.write( "Total?________________________(3/2)x__________________2d=4x\r<BR>\n" );
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document.write( "SPEED is distance divided by time:<BR>\n" );
document.write( "We want total distance and total time.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%284x%29%2F%28%283%2F2%29x%29=4%2F%283%2F2%29=%284%2A2%29%2F3=8%2F3=highlight%282%262%2F3%29 ALIGN=MIDDLE  ALT=\"%284x%29%2F%28%283%2F2%29x%29=4%2F%283%2F2%29=%284%2A2%29%2F3=8%2F3=highlight%282%262%2F3%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > mph.<BR>\n" );
document.write( "This is a little greater than what value you expected.<BR>\n" );
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