document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=145541>Question 145541</A>: <I><SPAN STYLE=\"word-break: break-all;\"> My mind has gone blank....any help is greatly appreciated:\r<BR>\n" );
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document.write( "A boat has a speed of 5 mph in still water.  The boat can travel 21 miles with the current in the same time in which it can travel 9 miles against the current.  Find the rate 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 #106196 by </B><A HREF=/tutors/aboutme.mpl?userid=edjones><B>edjones(8007)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=edjones><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=edjones><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=106196\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> d=r*t<BR>\n" );
document.write( "t=d/r<BR>\n" );
document.write( "Let x be the rate of the current.<BR>\n" );
document.write( "21/(5+x)=9/(5-x)<BR>\n" );
document.write( "21(5-x)=9(5+x) Multiply each side by the LCM to eliminate fractions.<BR>\n" );
document.write( "105-21x=45+9x<BR>\n" );
document.write( "60=30x<BR>\n" );
document.write( "x=2 mph<BR>\n" );
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document.write( "Check:<BR>\n" );
document.write( "21/7=3 hrs<BR>\n" );
document.write( "9/3=3 hrs<BR>\n" );
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document.write( "Ed\r<BR>\n" );
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