document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=146133>Question 146133</A>: <I><SPAN STYLE=\"word-break: break-all;\"> on a weekend outing, bernard rents a motorboat for 10 hours to travel down the river and back. The rental operator tells him to go for 4 hours downstream, leaving 6 hours to return upstream. \r<BR>\n" );
document.write( "\n" );
document.write( "If the river current flows at a speed of 4mph how fast must Bernard teavel in order to return in 10 hours?\r<BR>\n" );
document.write( "\n" );
document.write( "How far downstream did Bernard go before he turned back? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #106684 by </B><A HREF=/tutors/aboutme.mpl?userid=dealkit><B>dealkit(1)</B></A><img src=\"/images/stars/iconNewId_16x16.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=dealkit><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=106684\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Assume the boat speed is Xmph<BR>\n" );
document.write( "the river speed is 4mph\r<BR>\n" );
document.write( "\n" );
document.write( "Since the operators asked him to turn back after 4 hours<BR>\n" );
document.write( "  and return journey will take 6 hours<BR>\n" );
document.write( "   (remember that the speed is added in one way, and reduced in return)\r<BR>\n" );
document.write( "\n" );
document.write( "   (x+4) * 4 = (x-4) * 6<BR>\n" );
document.write( "   4x+16     = 6x-24<BR>\n" );
document.write( "   2x        = 40<BR>\n" );
document.write( "    x        = 20\r<BR>\n" );
document.write( "\n" );
document.write( "   speed of boat must be 20mph<BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );