document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1007823>Question 1007823</A>: <I><SPAN STYLE=\"word-break: break-all;\"> This word problem is a doozy. Anyone got any ideas? \r<BR>\n" );
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document.write( "A boat traveled 252 miles downstream and back. The trip downstream took 12 hours. The trip back took 36 hours. What is the speed of the boat in still water? What is the speed of 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 #623654 by </B><A HREF=/tutors/aboutme.mpl?userid=fractalier><B>fractalier(6550)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=fractalier><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=fractalier><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=623654\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> No worries.  Remember that rate times time equals distance, or rt=d.<BR>\n" );
document.write( "Let us call the rate in still water, r.<BR>\n" );
document.write( "Let us call the rate of the current, c.<BR>\n" );
document.write( "Then, from the facts in the problem we have<BR>\n" );
document.write( "(r+c)(12) = 252  and<BR>\n" );
document.write( "(r-c)(36) = 252<BR>\n" );
document.write( "We can multiply these out and get<BR>\n" );
document.write( "12r + 12c = 252  and<BR>\n" );
document.write( "36r - 36c = 252<BR>\n" );
document.write( "Now multiply the top one by three and add it to the second one...we get<BR>\n" );
document.write( "36r - 36c = 252<BR>\n" );
document.write( "+(36r + 36c = 756)<BR>\n" );
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document.write( "72r = 1008<BR>\n" );
document.write( "Now divide by 72 and get<BR>\n" );
document.write( "r = 14 miles per hour<BR>\n" );
document.write( "c can be found by substituting into the very first equation...<BR>\n" );
document.write( "(14+c)(12)=252<BR>\n" );
document.write( "Divide by 12 and get<BR>\n" );
document.write( "14 + c = 21<BR>\n" );
document.write( "c = 7 mph<BR>\n" );
document.write( "Ta-daa! </SPAN>\n" );
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