document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1057326>Question 1057326</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Carol requires 3 hours to go downstream 21 miles in her motorized boat. Her return trip upstream requires 3 1/2 hours. Assuming that Carol's boat motor runs at a constant pace, find the speed of her boat 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 #672368 by </B><A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><B>josgarithmetic(39623)</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=672368\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> No; her motorboat does not run at a constant pace.<BR>\n" );
document.write( "If you will describe this exercise correctly, I will solve most of it for you.\r<BR>\n" );
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document.write( "I see how this SHOULD be written:<BR>\n" );
document.write( "Carol requires 3 hours to go downstream 21 miles in her motorboat.  Her return trip upstream requires 3 1/2 hours. Find the speed of her motorboat in still water.\r<BR>\n" );
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document.write( "The \"assuming\" part is wrong.\r<BR>\n" );
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document.write( "Let c be the speed of the river current.\r<BR>\n" );
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document.write( "SETUP TABLE OF DATA\r<BR>\n" );
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document.write( "                       speed        time        distance\r\n" );
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document.write( "DOWN                   r+c          3            21\r\n" );
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document.write( "UP                     r-c         <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=3%261%2F2 ALIGN=MIDDLE  ALT=\"3%261%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" >        21\r\n" );
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document.write( "CREATE SYSTEM OF EQUATIONS USING TRAVEL RATE RULE\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=system%28%28r%2Bc%29%2A3=21%2C%28r-c%29%283%261%2F2%29=21%29 ALIGN=MIDDLE  ALT=\"system%28%28r%2Bc%29%2A3=21%2C%28r-c%29%283%261%2F2%29=21%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "SOLVE THE SYSTEM FOR THE UNKNOWN VARIABLES<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=system%28r%2Bc=7%2Cr-c=3%2F2%29 ALIGN=MIDDLE  ALT=\"system%28r%2Bc=7%2Cr-c=3%2F2%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=r%2Bc%2Br-c=7%2B3%2F2 ALIGN=MIDDLE  ALT=\"r%2Bc%2Br-c=7%2B3%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2r=%2814%2B3%29%2F2 ALIGN=MIDDLE  ALT=\"2r=%2814%2B3%29%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight%28r=17%2F4%29 ALIGN=MIDDLE  ALT=\"highlight%28r=17%2F4%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >----------and this is what the question asked for.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%284%261%2F4%29%28miles%2Fhour%29 ALIGN=MIDDLE  ALT=\"%284%261%2F4%29%28miles%2Fhour%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >. </SPAN>\n" );
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