document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=901866>Question 901866</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A boat can travel six miles downstream in 40 minutes. The return trip requires an hour. Find the rate of the boat 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 #546991 by </B><A HREF=/tutors/aboutme.mpl?userid=lwsshak3><B>lwsshak3(11628)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=lwsshak3><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=546991\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A boat can travel six miles downstream in 40 minutes. The return trip requires an hour. Find the rate of the boat in still water. <BR>\n" );
document.write( "***<BR>\n" );
document.write( "let x=speed of boat in  still water<BR>\n" );
document.write( "let c=speed of current<BR>\n" );
document.write( "x+c=speed of boat downstream<BR>\n" );
document.write( "x-c=speed of boat upstream<BR>\n" );
document.write( "travel time*speed=distance<BR>\n" );
document.write( "..<BR>\n" );
document.write( "40 min=2/3 hr<BR>\n" );
document.write( "2/3*(x+c)=6<BR>\n" );
document.write( "1*(x-c)=6<BR>\n" );
document.write( "..<BR>\n" );
document.write( "2x+2c=18<BR>\n" );
document.write( "x-c=6<BR>\n" );
document.write( "..<BR>\n" );
document.write( "2x+2c=18<BR>\n" );
document.write( "2x-2c=12<BR>\n" );
document.write( "add<BR>\n" );
document.write( "4x=30<BR>\n" );
document.write( "x=7.5<BR>\n" );
document.write( "c=x-6=1.5<BR>\n" );
document.write( "rate of the boat in still water=7.5 mph </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );