document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1191430>Question 1191430</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A river is flowing downstream at rate of 2km/h. <BR>\n" );
document.write( "Murray can swim at a rate of 3km/h. <BR>\n" );
document.write( "Murray jumps in and swims downstream for a certain distance then turns around and swims upstream back to the start. In total it takes 30 minutes. <BR>\n" );
document.write( "How far did Murray swim downstream?\r<BR>\n" );
document.write( "\n" );
document.write( "I got 15/16 km but the answer is 5/12 km. How did it get to 5/12km? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #823220 by </B><A HREF=/tutors/aboutme.mpl?userid=greenestamps><B>greenestamps(13200)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=greenestamps><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=greenestamps><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=823220\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <br><BR>\n" );
document.write( "His downstream rate is 5km/h; his upstream speed is 1km/h.<br><BR>\n" );
document.write( "If the distance in kilometers is d, then a traditional algebraic approach would look something like this:<br><BR>\n" );
document.write( "time downstream = d/5<BR>\n" );
document.write( "time upstream = d/1 = d<br><BR>\n" );
document.write( "The total time was 30 minutes, which is 1/2 hour:<br><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d%2F5%2Bd=1%2F2 ALIGN=MIDDLE  ALT=\"d%2F5%2Bd=1%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><br><BR>\n" );
document.write( "Multiply by 10 to clear fractions:<br><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2d%2B10d=5 ALIGN=MIDDLE  ALT=\"2d%2B10d=5\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=12d=5 ALIGN=MIDDLE  ALT=\"12d=5\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d=5%2F12 ALIGN=MIDDLE  ALT=\"d=5%2F12\"   DISABLED_style= \"max-width:90%; height:auto;\" ><br><BR>\n" );
document.write( "ANSWER: 5/12 km<br><BR>\n" );
document.write( "I personally prefer a different solution method:<br><BR>\n" );
document.write( "His downstream rate of 5km/h is 5 times his upstream speed; since the distances downstream and back are the same, he spends 5 times much time coming upstream as going downstream.  That means he spends 1/6 of the total time going downstream and 5/6 of his total time coming back upstream.<br><BR>\n" );
document.write( "Now use either the downstream or upstream speeds and times to find the distance.<br><BR>\n" );
document.write( "Downstream:<br><BR>\n" );
document.write( "1/6 of 30 minutes, or 1/6 of 1/2 hour, is 1/12 hour; 1/12 hour at 5km/h is (5)(1/12) = 5/12 km.<br><BR>\n" );
document.write( "or...<br><BR>\n" );
document.write( "Upstream:<br><BR>\n" );
document.write( "5/6 of 1/2 hour is 5/12 hour; 5/12 of an hour at 1km/h is (1)(5/12) = 5/12 km.<br><BR>\n" );
document.write( " </SPAN>\n" );
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