document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=773927>Question 773927</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A riverboat can travel 30km downstream in 3 hrs & can make the return trip in 5 hrs. Find the speed of the boat and the speed of the current. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #471930 by </B><A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><B>josgarithmetic(39617)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=471930\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The return trip is upstream, the lesser rate.  The downstream trip is the greater rate.\r<BR>\n" );
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document.write( "Let r = riverboat speed if no current.<BR>\n" );
document.write( "Let c = speed of the current.\r<BR>\n" );
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document.write( "DIRECTION_______speed_________time______distance<BR>\n" );
document.write( "UPSTREM_________r-c___________5__________30<BR>\n" );
document.write( "DOWNSTREAM______r+c___________3__________30\r<BR>\n" );
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document.write( "Basic concept is rate*time=distance.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28r-c%295=30 ALIGN=MIDDLE  ALT=\"%28r-c%295=30\"   DISABLED_style= \"max-width:90%; height:auto;\" > and <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28r%2Bc%293=30 ALIGN=MIDDLE  ALT=\"%28r%2Bc%293=30\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Two equations and two unknowns, r and c.  Solve the system. </SPAN>\n" );
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