document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1045497>Question 1045497</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Maricris rides her power boat up and down the Agno river. The water in the river flows at 6 miles per hour. Maricris takes 5 hours longer to travel 360 miles against the current than she does to travel 360 miles along with the current. What is the speed of Maricris 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 #660943 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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=660943\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Maricris rides her power boat up and down the Agno river. The water in the river flows at 6 miles per hour. Maricris takes 5 hours longer to travel 360 miles against the current than she does to travel 360 miles along with the current. What is the speed of Maricris boat in still water? <BR>\n" );
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document.write( "Upstream DATA:<BR>\n" );
document.write( "dist = 360 miles ; time = x+5 hrs ; rate = d/t = 360/(x+5) mph<BR>\n" );
document.write( "---<BR>\n" );
document.write( "Downstream DATA:<BR>\n" );
document.write( "dist = 360 miles ; time = x hrs ; rate = 360/x mph<BR>\n" );
document.write( "--------------<BR>\n" );
document.write( "Equation:<BR>\n" );
document.write( "rate - rate = 6 mph<BR>\n" );
document.write( "360/x - 360/(x+5) = 6<BR>\n" );
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document.write( "360x + 360*5 - 360x = 6x(x+5)<BR>\n" );
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document.write( "6x^2 + 30x - 5*360 = 0<BR>\n" );
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document.write( "x^2 + 5x - 300 = 0<BR>\n" );
document.write( "(x+20)(x-15) = 0 <BR>\n" );
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document.write( "Positive solution:<BR>\n" );
document.write( "x = 15 hrs<BR>\n" );
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document.write( "rate upstream = 360/(x+5) = 360/20 = 18 mph<BR>\n" );
document.write( "rate downstream = 360/x = 360/15 = 24 mph<BR>\n" );
document.write( "--------------<BR>\n" );
document.write( "Equation:<BR>\n" );
document.write( "boat speed + current = 24 mph<BR>\n" );
document.write( "b + 6 = 24<BR>\n" );
document.write( "b = 18 mph (boat speed in calm water)<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );