document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=769071>Question 769071</A>: <I><SPAN STYLE=\"word-break: break-all;\"> For a portion of the Green River in Utah, the rate of the river's current is 4 mph. A tour guide can row 6 mi down this river and back in 2 h. Find the rowing rate of the guide in calm water.\r<BR>\n" );
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document.write( "I'm having a hard time recalling how o set up a problem like this. I have tried:<BR>\n" );
document.write( "with current distance: 6mi<BR>\n" );
document.write( "with current rate: x+4<BR>\n" );
document.write( "with current time: 6/x+4\r<BR>\n" );
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document.write( "Against current distance: 6mi<BR>\n" );
document.write( "against current rate: x-4<BR>\n" );
document.write( "against current time: 6/x-4\r<BR>\n" );
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document.write( "I'm unsure of how to set this up exactly with all this data or if I am even on the right track. Thanks for any help.<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 #468657 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=468657\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Make a speed, time, distance table for all of the data and any that you can express from the given data.\r<BR>\n" );
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document.write( "Let r = speed of the guide if rowing in still water.<BR>\n" );
document.write( "When you say, \"6 mi down the river and back\", this is 6 miles up the river and 6 miles down the river.  Round trip up and back is 12 miles.  If you believe this is the wrong interpretation then say so.\r<BR>\n" );
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document.write( "DIRECTION________speed___________time hours________distance miles<BR>\n" );
document.write( "DOWN RIVER_______r+4_____________(___)________________6<BR>\n" );
document.write( "UP RIVER_________r-4_____________(___)________________6\r<BR>\n" );
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document.write( "The key relation speed*time=distance allows us to make expressions to fill-in times.  <BR>\n" );
document.write( "r*h=d for <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=speed%2AtimeHours=distanceMiles ALIGN=MIDDLE  ALT=\"speed%2AtimeHours=distanceMiles\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=timeHours=distanceMiles%2Fspeed ALIGN=MIDDLE  ALT=\"timeHours=distanceMiles%2Fspeed\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "DIRECTION________speed___________time hours________distance miles<BR>\n" );
document.write( "DOWN RIVER_______r+4_____________(6/(r+4))________________6<BR>\n" );
document.write( "UP RIVER_________r-4_____________(6/(r-4))________________6<BR>\n" );
document.write( "TOTAL______________________________2_____________________12\r<BR>\n" );
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document.write( "He rows up and back in 2 hours.  This allows us to equate to the sum of the time expressions and the only unknown variable is r.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight%286%2F%28r%2B4%29%2B6%2F%28r-4%29=2%29 ALIGN=MIDDLE  ALT=\"highlight%286%2F%28r%2B4%29%2B6%2F%28r-4%29=2%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > The problem's principle resulting equation to solve.  The rest of the process is for you to do. </SPAN>\n" );
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