document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=439292>Question 439292</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A college crew team can maintain a speed equivalent to 15 km/hr in still water. If it takes the team 50 minutes to row 6 km upstream and back, what is the rate of the current in the river?\r<BR>\n" );
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document.write( "my teacher gave me the answer 3km/hr but i cant figure out how to set it up. could you also explain as you go through? thank you very much :D </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #303552 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=303552\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A college crew team can maintain a speed equivalent to 15 km/hr in still water. If it takes the team 50 minutes to row 6 km upstream and back, what is the rate of the current in the river?<BR>\n" );
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document.write( "upstream DATA:<BR>\n" );
document.write( "distance = 6 km ; rate = 15-c ; time = d/r = 6/(15-c) hrs.<BR>\n" );
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document.write( "downstream DATA:<BR>\n" );
document.write( "distance = 6 km ; rate = 15+c ; time = d/r = 6/(15+c) hrs<BR>\n" );
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document.write( "Equation:<BR>\n" );
document.write( "time + time =  (5/6) hr<BR>\n" );
document.write( "6/(15-c) + 6/(15+c) = (5/6) hr<BR>\n" );
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document.write( "6*6(15+c) + 6*6(15-c) = 5*(225-c^2)<BR>\n" );
document.write( "1080 = 5(225-c^2)<BR>\n" );
document.write( "216 = 225-c^2<BR>\n" );
document.write( "c^2 = 9<BR>\n" );
document.write( "Positive solution:<BR>\n" );
document.write( "c = 3 km/hr (speed of the current)<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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document.write( "my teacher gave me the answer 3km/hr  </SPAN>\n" );
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