document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=952059>Question 952059</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A river is flowing downstream at a rate of 2 metres per second. Brendan, who has an average swimming speed of 3 metres per second, decides to go for a swim in the river. He dives into the river and swims downstream to a certain point then swims back upstream to the starting point. The total time taken is 4 minutes. How far did Brendan swim downstream?\r<BR>\n" );
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document.write( "Please show working </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #581448 by </B><A HREF=/tutors/aboutme.mpl?userid=josmiceli><B>josmiceli(19441)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=josmiceli><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=josmiceli><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=581448\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The current, <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+c+=+2+ ALIGN=MIDDLE  ALT=\"+c+=+2+\"   DISABLED_style= \"max-width:90%; height:auto;\" > m/sec<BR>\n" );
document.write( "Swimming speed is <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+s+=+3+ ALIGN=MIDDLE  ALT=\"+s+=+3+\"   DISABLED_style= \"max-width:90%; height:auto;\" > m/sec<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+3+%2B+2+=+5+ ALIGN=MIDDLE  ALT=\"+3+%2B+2+=+5+\"   DISABLED_style= \"max-width:90%; height:auto;\" > m/sec downstream<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+3+-+2+=+1+ ALIGN=MIDDLE  ALT=\"+3+-+2+=+1+\"   DISABLED_style= \"max-width:90%; height:auto;\" > m/sec upstream<BR>\n" );
document.write( "----------------------------------<BR>\n" );
document.write( "Let <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+d+ ALIGN=MIDDLE  ALT=\"+d+\"   DISABLED_style= \"max-width:90%; height:auto;\" > = one-way distance he swims<BR>\n" );
document.write( "Let <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+t+ ALIGN=MIDDLE  ALT=\"+t+\"   DISABLED_style= \"max-width:90%; height:auto;\" > = his time in minutes to go downstream<BR>\n" );
document.write( "Convert <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+4+ ALIGN=MIDDLE  ALT=\"+4+\"   DISABLED_style= \"max-width:90%; height:auto;\" > min to sec<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+4%2A60+=+240+ ALIGN=MIDDLE  ALT=\"+4%2A60+=+240+\"   DISABLED_style= \"max-width:90%; height:auto;\" > sec<BR>\n" );
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document.write( "Equation for downstream:<BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+d+=+5%2At+ ALIGN=MIDDLE  ALT=\"+d+=+5%2At+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Equation for upstream:<BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+d+=+1%2A%28+240+-+t+%29+ ALIGN=MIDDLE  ALT=\"+d+=+1%2A%28+240+-+t+%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "-----------------------<BR>\n" );
document.write( "Substitute (1) into (2)<BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+5t+=+240+-+t+ ALIGN=MIDDLE  ALT=\"+5t+=+240+-+t+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+6t+=+240+ ALIGN=MIDDLE  ALT=\"+6t+=+240+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+t+=+40+ ALIGN=MIDDLE  ALT=\"+t+=+40+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "and<BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+d+=+5%2At+ ALIGN=MIDDLE  ALT=\"+d+=+5%2At+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+d+=+5%2A40+ ALIGN=MIDDLE  ALT=\"+d+=+5%2A40+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+d+=+200+ ALIGN=MIDDLE  ALT=\"+d+=+200+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "He swam 200 m<BR>\n" );
document.write( "----------------<BR>\n" );
document.write( "check:<BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+d+=+1%2A%28+240+-+t+%29+ ALIGN=MIDDLE  ALT=\"+d+=+1%2A%28+240+-+t+%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+200+=+1%2A%28+240+-+40+%29+ ALIGN=MIDDLE  ALT=\"+200+=+1%2A%28+240+-+40+%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" > <BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+200+=+200+ ALIGN=MIDDLE  ALT=\"+200+=+200+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "OK<BR>\n" );
document.write( " </SPAN>\n" );
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