document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=142297>Question 142297</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A boat travels 20 miles upstream in the same time that it would take to travel 30 miles downstream. If the rate of the water is 5 miles per hour, find the speed of the boat alone. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #103613 by </B><A HREF=/tutors/aboutme.mpl?userid=ptaylor><B>ptaylor(2198)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ptaylor><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=ptaylor><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=103613\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <BR>\n" );
document.write( "Distance(d) equals Rate(r) times Time(t) or d=rt; r=d/t and t=d/r\r<BR>\n" );
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document.write( "Let r= rate of the boat in still water<BR>\n" );
document.write( "r-5=rate of the boat upsteam <BR>\n" );
document.write( "r+5=rate of the boat downstream\r<BR>\n" );
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document.write( "Time to travel upstream=20/(r-5)<BR>\n" );
document.write( "Time to travel downstream=30/(r+5)\r<BR>\n" );
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document.write( "Now we are told that the above two times are equal, so:\r<BR>\n" );
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document.write( "20/(r-5)=30/(r+5) multiply each term by (r-5)(r+5) or cross-multiply and we get:\r<BR>\n" );
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document.write( "20(r+5)=30(r-5)  get rid of parens\r<BR>\n" );
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document.write( "20r+100=30r-150  subtract 30r and also 100 from each side<BR>\n" );
document.write( "20r-30r+100-100=30r-30r-150-100  collect like terms\r<BR>\n" );
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document.write( "-10r=-250  divide each side by -10\r<BR>\n" );
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document.write( "r=25 mph-----rate of boat in still water\r<BR>\n" );
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document.write( "CK\r<BR>\n" );
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document.write( "20/(25-5)=30/(25+5)<BR>\n" );
document.write( "20/20=30/30<BR>\n" );
document.write( "1=1\r<BR>\n" );
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document.write( "Hope this helps---ptaylor </SPAN>\n" );
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