document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=550196>Question 550196</A>: <I><SPAN STYLE=\"word-break: break-all;\"> please help me solve this:\r<BR>\n" );
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document.write( "If he population of a city doubles every 20 years, how long does it take to triple? (state this is logarithmic form and find solution)\r<BR>\n" );
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document.write( "please, i really need your help!\r<BR>\n" );
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document.write( "Thanks in advance </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #358549 by </B><A HREF=/tutors/aboutme.mpl?userid=Alan3354><B>Alan3354(69443)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Alan3354><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=Alan3354><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=358549\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> If he population of a city doubles every 20 years, how long does it take to triple? (state this is logarithmic form and find solution)<BR>\n" );
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document.write( "FP = PP*2^t (FP = future Pop, PP = present Pop, t in 20 year periods)<BR>\n" );
document.write( "For FP = 3PP:<BR>\n" );
document.write( "2^t = 3<BR>\n" );
document.write( "t*log(2) = log(3)<BR>\n" );
document.write( "t = log(3)/log(2)<BR>\n" );
document.write( "# of years = 20t = 20log(3)/log(2)<BR>\n" );
document.write( "years =~ 31.699<BR>\n" );
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document.write( "You can use logs or ln, doesn't matter.<BR>\n" );
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