document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=578197>Question 578197</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Given a starting population of 100 bacteria, the formula b=100(2^t) can be used to find the number of bacteria, \"b\", after \"t\" periods of time. If each period is 15 minutes long, how many minutes will it take for the population of bacteria to reach 51,200?<BR>\n" );
document.write( "i already know the answer is 135...but how do you get that? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #370544 by </B><A HREF=/tutors/aboutme.mpl?userid=dfrazzetto><B>dfrazzetto(283)</B></A><img src=\"/images/stars/stars-09.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=dfrazzetto><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=dfrazzetto><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=370544\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <BR>\n" );
document.write( "b=100(2^t)\r<BR>\n" );
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document.write( "51,200 = 100 (2^t)   \r<BR>\n" );
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document.write( "512 = 2^t\r<BR>\n" );
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document.write( "**take the log(base 2) of both sides\r<BR>\n" );
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document.write( "log(512) = log (2^t)\r<BR>\n" );
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document.write( "9 = t\r<BR>\n" );
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document.write( "so 9 'periods' of time, to get minutes:\r<BR>\n" );
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document.write( "minutes = 15t = 15 x 9 = 135 minutes\r<BR>\n" );
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document.write( " </SPAN>\n" );
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