document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1155687>Question 1155687</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A boat travelling upstream goes 84 kilometers in 7 hours. If the return trip takes only 3 hours, what is the speed (in kilometers per hour) of the boat in still water?\r<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 #778313 by </B><A HREF=/tutors/aboutme.mpl?userid=Boreal><B>Boreal(15235)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Boreal><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=Boreal><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=778313\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> current is c<BR>\n" );
document.write( "speed is s<BR>\n" );
document.write( "distance=s*time\r<BR>\n" );
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document.write( "it goes upstream (s-c)=12 km/h <BR>\n" );
document.write( "it goes downstream (s+c)=28 km/h (84/3)<BR>\n" );
document.write( "therefore, <BR>\n" );
document.write( "s-c=12<BR>\n" );
document.write( "s+c=28<BR>\n" );
document.write( "2s=40<BR>\n" );
document.write( "s=20 km/h ANSWER<BR>\n" );
document.write( "c=8 km/h<BR>\n" );
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