document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=83738>Question 83738</A>: <I><SPAN STYLE=\"word-break: break-all;\"> For a certain strain of bacteria, the number of bacteria present after t hours is given by the equation: Q =  Q(0)e^0.42t  where Q(0) represents the initial number of bacteria. How long will it take 700 bacteria to increase to 7,000 bacteria?  Express to the nearest tenth. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #60219 by </B><A HREF=/tutors/aboutme.mpl?userid=lekelly><B>lekelly(20)</B></A><img src=\"/images/stars/stars-06.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=lekelly><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=60219\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A=Pe^(rt)<BR>\n" );
document.write( "7000=700e^.42t\r<BR>\n" );
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document.write( "Solve for t:<BR>\n" );
document.write( "7000/700=700/700e^.42t=<BR>\n" );
document.write( "10=e^.42t<BR>\n" );
document.write( "take the log of each side:<BR>\n" );
document.write( "ln(10)=ln(e^.42t)  knowing the rules ln(e^rt)=rt  therefore:<BR>\n" );
document.write( "ln(10)=.42t<BR>\n" );
document.write( "ln(10)/.42=t<BR>\n" );
document.write( "ln(10)=2.3025/.42=\r<BR>\n" );
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document.write( "5.48=t  YOUR ANSWER </SPAN>\n" );
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