document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=979179>Question 979179</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A  barge  movers  12  miles  downstream  and  8  miles  upstream  in  a  total<BR>\n" );
document.write( "time of 2 hours.  The current in the river is 2 mph.  How fast does the barge<BR>\n" );
document.write( "move in still water? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #600560 by </B><A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><B>josgarithmetic(39620)</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=600560\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Saying that all with variables:<BR>\n" );
document.write( "A  barge  movers  D  miles  downstream  and  d  miles  upstream  in  a  total<BR>\n" );
document.write( "time of h hours.  The current in the river is k mph.  How fast does the barge<BR>\n" );
document.write( "move in still water (let this unknown rate be r) ?\r<BR>\n" );
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document.write( "____________________rate___________time___________distance<BR>\n" );
document.write( "DOWN________________r+k____________(____)_________D<BR>\n" );
document.write( "UPST________________r-k___________(_____)_________d<BR>\n" );
document.write( "Total______________________________T\r<BR>\n" );
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document.write( "Use the uniform rates travel rule to fill the missing time cells in the table <BR>\n" );
document.write( "according to <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28rate%29%28time%29=distance ALIGN=MIDDLE  ALT=\"%28rate%29%28time%29=distance\"   DISABLED_style= \"max-width:90%; height:auto;\" >.\r<BR>\n" );
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document.write( "____________________rate___________time___________distance<BR>\n" );
document.write( "DOWN________________r+k____________D/(r+k)_________D<BR>\n" );
document.write( "UPST________________r-k____________d/(r-k)_________d<BR>\n" );
document.write( "Total_______________________________T\r<BR>\n" );
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document.write( "Resulting equation is <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=D%2F%28r%2Bk%29%2Bd%2F%28r-k%29=T ALIGN=MIDDLE  ALT=\"D%2F%28r%2Bk%29%2Bd%2F%28r-k%29=T\"   DISABLED_style= \"max-width:90%; height:auto;\" >.  This has the single UNKNOWN variable, r.  Solve the equation for r.\r<BR>\n" );
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document.write( "Once that is accomplished, you have the variables assigned as<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=system%28D=12%2Cd=8%2CT=2%2Ck=2%29 ALIGN=MIDDLE  ALT=\"system%28D=12%2Cd=8%2CT=2%2Ck=2%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >.<BR>\n" );
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document.write( "Substitute those and evaluate r. </SPAN>\n" );
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