document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=316631>Question 316631</A>: <I><SPAN STYLE=\"word-break: break-all;\"> If a boat travels downstream for one hour and travels twelve miles and returns upstream to the starting point and the trip requires four hours how fast is 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 #226637 by </B><A HREF=/tutors/aboutme.mpl?userid=mananth><B>mananth(16946)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=mananth><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=mananth><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=226637\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> let speed of current be x mph\r<BR>\n" );
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document.write( "speed downstream = 12 mph<BR>\n" );
document.write( "speed in still water = 12-x<BR>\n" );
document.write( "speed upstream = 12-2x<BR>\n" );
document.write( "..<BR>\n" );
document.write( "time taken down stream = 1 hour<BR>\n" );
document.write( "time taken upstream = 3 hours<BR>\n" );
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document.write( "distance = speed * time<BR>\n" );
document.write( "distance upstream + distance down stream = total distance<BR>\n" );
document.write( "..<BR>\n" );
document.write( "12+3(12-2x)=24<BR>\n" );
document.write( "12+36-6x=24<BR>\n" );
document.write( "12+36-24=6x<BR>\n" );
document.write( "24=6x<BR>\n" );
document.write( "x=4 mph </SPAN>\n" );
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