document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=347047>Question 347047</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Mike & Bill row their boat (constant speed) 55mi downstream for 2.5hrs, helped by the current. Rowing at the same rate, the trip back against the current takes 5.5hrs. Find the rate 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 #248160 by </B><A HREF=/tutors/aboutme.mpl?userid=ptaylor><B>ptaylor(2198)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ptaylor><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=ptaylor><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=248160\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Distance(d) equals Rate(r) times Time(t) or d=rt; r=d/t and t=d/r<BR>\n" );
document.write( "Let R=rate of boat in still water<BR>\n" );
document.write( "and let r=rate of current<BR>\n" );
document.write( "(DOWNSTREAM WE ADD THE RATE OF THE CURRENT; UPSTREAM, WE SUBTRACT)<BR>\n" );
document.write( "Downstream:<BR>\n" );
document.write( "R+r=55/(2.5)=22-------------------eq1<BR>\n" );
document.write( "Upstream:<BR>\n" );
document.write( "R-r=55/(5.5)=10------------------eq2\r<BR>\n" );
document.write( "\n" );
document.write( "add eq1 and eq2:<BR>\n" );
document.write( "2R=32<BR>\n" );
document.write( "R=16 mph---speed of boat ---substitute into eq1 and we get:<BR>\n" );
document.write( "r=22-16=6 mph---speed of current<BR>\n" );
document.write( "CK<BR>\n" );
document.write( "2.5*22=55<BR>\n" );
document.write( "5.5*10=55<BR>\n" );
document.write( "Hope this helps--ptaylor </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );