document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=387782>Question 387782</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A speedboat takes 4 hours longer to go 80 miles up a river than to return. If the boat cruises at 15 miles per hour in still water, what is the rate of the current? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #275599 by </B><A HREF=/tutors/aboutme.mpl?userid=Fombitz><B>Fombitz(32388)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Fombitz><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/cgi-bin/show-face.mpl?user=Fombitz><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=275599\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Rate*Time=Distance<BR>\n" );
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document.write( "Let the current speed be C.<BR>\n" );
document.write( "With the current,<BR>\n" );
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document.write( "Against the current,<BR>\n" );
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document.write( "Subsituting,<BR>\n" );
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document.write( "Use the common denominator, <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%2815-C%29%2815%2BC%29 ALIGN=MIDDLE  ALT=\"%2815-C%29%2815%2BC%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
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document.write( "Only one solution since <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=C%3E=0 ALIGN=MIDDLE  ALT=\"C%3E=0\"   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=highlight%28C=5%29 ALIGN=MIDDLE  ALT=\"highlight%28C=5%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >mph\r<BR>\n" );
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document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );