document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=360415>Question 360415</A>: <I><SPAN STYLE=\"word-break: break-all;\"> It took Lance and Ivan 6 hours to travel 33 miles downstream by canoe.The next day the travelled upstream for 8 hours for 20 miles.What was the rate of the current? What was their average speed in still water? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #257206 by </B><A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><B>ankor@dixie-net.com(22740)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><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=ankor@dixie-net.com><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=257206\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> It took Lance and Ivan 6 hours to travel 33 miles downstream by canoe.<BR>\n" );
document.write( "The next day the traveled upstream for 8 hours for 20 miles.<BR>\n" );
document.write( "What was the rate of the current?<BR>\n" );
document.write( " What was their average speed in still water?<BR>\n" );
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document.write( "Let s = their speed in still water<BR>\n" );
document.write( "Let c = rate of the current<BR>\n" );
document.write( "then<BR>\n" );
document.write( "(s+c) = effective speed downstream<BR>\n" );
document.write( "and<BR>\n" );
document.write( "(s-c) = effective speed upstream<BR>\n" );
document.write( ":<BR>\n" );
document.write( "Write two distance equations, dist = time * speed<BR>\n" );
document.write( ":<BR>\n" );
document.write( "6(s+c) = 33<BR>\n" );
document.write( "8(s-c) = 20<BR>\n" );
document.write( "which is<BR>\n" );
document.write( "6s + 6c = 33<BR>\n" );
document.write( "8s - 8c = 20<BR>\n" );
document.write( ":<BR>\n" );
document.write( "Use elimination here, multiply the 1st equation by 8, the 2nd equation by 6<BR>\n" );
document.write( "48s + 48c = 264<BR>\n" );
document.write( "48s - 48c = 120<BR>\n" );
document.write( "-------------------addition eliminates c, find s<BR>\n" );
document.write( "96s = 384<BR>\n" );
document.write( "s = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=384%2F96 ALIGN=MIDDLE  ALT=\"384%2F96\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "s = 4 mph in still water<BR>\n" );
document.write( ":<BR>\n" );
document.write( "Find s: using: 6s + 6c = 33<BR>\n" );
document.write( "6(4) + 6c = 33<BR>\n" );
document.write( "6c = 33 - 24<BR>\n" );
document.write( "6c = 9<BR>\n" );
document.write( "c = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=9%2F6 ALIGN=MIDDLE  ALT=\"9%2F6\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "c = 1.5 mph is the current<BR>\n" );
document.write( ":<BR>\n" );
document.write( ":<BR>\n" );
document.write( "Check these solutions in the 2nd equation 8(s-c) = 20<BR>\n" );
document.write( "8(4 - 1.5) = <BR>\n" );
document.write( "8 * 2.5 = 20; confirms our solutions </SPAN>\n" );
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