document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=978185>Question 978185</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A certain bacteria population is known to doubles every 90 minutes. Suppose that there are initially 160 bacteria. \r<BR>\n" );
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document.write( "What is the size of the population after  t  hours? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #599641 by </B><A HREF=/tutors/aboutme.mpl?userid=Boreal><B>Boreal(15235)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Boreal><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=Boreal><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=599641\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A=160(1+r)^t<BR>\n" );
document.write( "320/160=2=(1+r)^t<BR>\n" );
document.write( "0.693=t ln (1 +r)<BR>\n" );
document.write( "0.693/1.5 = ln (1+r)<BR>\n" );
document.write( "0.462=ln (1+r)<BR>\n" );
document.write( "raise to e power both sides<BR>\n" );
document.write( "1.5872=1+r<BR>\n" );
document.write( "r=0.5872\r<BR>\n" );
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document.write( "A=160(1.5872)^t  ANSWER.\r<BR>\n" );
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document.write( "Expect quadrupling in 180 minutes or t=3\r<BR>\n" );
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document.write( "A=160(1.5872)^3=639.75 or rounded to 640.\r<BR>\n" );
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document.write( " </SPAN>\n" );
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