document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=67938>Question 67938</A>: <I><SPAN STYLE=\"word-break: break-all;\"> If a crew of 8 can row a boat 20k/hr in still water. The river flows 2K/hr. If they row the boat up stream and return in 15min.how far up stream did they go? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #48326 by </B><A HREF=/tutors/aboutme.mpl?userid=ptaylor><B>ptaylor(2198)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ptaylor><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=ptaylor><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=48326\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Let d=distance they rowed upstream\r<BR>\n" );
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document.write( "distance they rowed upstream = distance they rowed downstream\r<BR>\n" );
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document.write( "speed (rate) upstream equals speed of boat in still water (20k/hr) minus speed of current(2k/hr)=18k/hr\r<BR>\n" );
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document.write( "speed (rate) downstream equals speed of boat in still water (20k/hr) plus speed of current(2k/hr)=22k/hr\r<BR>\n" );
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document.write( "distance(d)=rate(r) times time (t) or d=rt and t=d/r\r<BR>\n" );
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document.write( "time upstream =d/18<BR>\n" );
document.write( "time downstream=d/22\r<BR>\n" );
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document.write( "Now we are told that time upstream (d/18) plus time downstream (d/22)=15 minutes or 0.25 hr.  so our equation to solve is\r<BR>\n" );
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document.write( "d/18+d/22=0.25  Multiply each term by (18)(22) to get rid of fractions\r<BR>\n" );
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document.write( "22d(18/18)+18d(22/22)=0.25(18)(22)  clear parens\r<BR>\n" );
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document.write( "22d+18d=99<BR>\n" );
document.write( "40d=99<BR>\n" );
document.write( "d=2.475 km---------------distance upstream\r<BR>\n" );
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document.write( "ck\r<BR>\n" );
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document.write( "(2.475)/18+(2.475)/22=0.25\r<BR>\n" );
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document.write( "0.1375+0.1125=0.25\r<BR>\n" );
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document.write( "0.25=0.25\r<BR>\n" );
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document.write( "Hope this helps----ptaylor\r<BR>\n" );
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document.write( " </SPAN>\n" );
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