document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=370513>Question 370513</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The riverboat Hiawatha goes 30 km upstream and back in 4 hours. If the Hiawatha's speed in still water is 16 km'h, what is 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 #264175 by </B><A HREF=/tutors/aboutme.mpl?userid=scott8148><B>scott8148(6628)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=scott8148><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=scott8148><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=264175\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> t = d / r ___ total time is 4 h\r<BR>\n" );
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document.write( "[30 / (16 - r)] + [30 / (16 + r)] = 4\r<BR>\n" );
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document.write( "480 + 30r + 480 - 30r = 1024 - 4r^2\r<BR>\n" );
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document.write( "r^2 - 16 = 0 </SPAN>\n" );
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