document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=742968>Question 742968</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I have been given a very challenging word problem and cannot figure it out.  It's on Finding rates.  Jeff bicycles 160 miles at the rate of r mph.  The same trip would have taken 2 hours longer if he had decreased his speed by 4 mph.  Find r.  Can you please help me solve this problem?...thanks </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #452706 by </B><A HREF=/tutors/aboutme.mpl?userid=mananth><B>mananth(16946)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=mananth><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=mananth><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=452706\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> d=160<BR>\n" );
document.write( "speed = r\r<BR>\n" );
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document.write( "t=160/r\r<BR>\n" );
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document.write( "d=160<BR>\n" );
document.write( "new speed = r-4\r<BR>\n" );
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document.write( "t= 160/(r-4)\r<BR>\n" );
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document.write( "time new speed time original speed = 2\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=160%2F%28r-4%29-160%2Fr=2 ALIGN=MIDDLE  ALT=\"160%2F%28r-4%29-160%2Fr=2\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "multiply by r(r-2)\r<BR>\n" );
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document.write( "160r-9600+160r= 2r(r-4)\r<BR>\n" );
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document.write( "320r-9600=2r^2-8r\r<BR>\n" );
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document.write( "2r^2-328r+9600=0\r<BR>\n" );
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document.write( "/2<BR>\n" );
document.write( "r^2-164r+4800=0\r<BR>\n" );
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document.write( "r^2-164r+6724=6724-4800\r<BR>\n" );
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document.write( "(r-82)^2=1924\r<BR>\n" );
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document.write( "r-82=43.86\r<BR>\n" );
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document.write( "r=82-43.86\r<BR>\n" );
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document.write( "r=38.14  </SPAN>\n" );
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