document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1126437>Question 1126437</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Bacteria are growing in a culture, and their number is increasing at the rate of 5 % an hour . Initially , 400 bacteria are present. <BR>\n" );
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document.write( "(a) Determine an equation that gives the numbet, N of bacteria present after t hours. \r<BR>\n" );
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document.write( "(b) How many bacteria are present after one hour and After four hour </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #742744 by </B><A HREF=/tutors/aboutme.mpl?userid=Theo><B>Theo(13342)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Theo><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=Theo><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=742744\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> the formula to use with this is f = p * (1 + r) ^ t\r<BR>\n" );
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document.write( "f is the future value<BR>\n" );
document.write( "p is the present value<BR>\n" );
document.write( "r is the interest rate per time period<BR>\n" );
document.write( "t is the number of time periods.\r<BR>\n" );
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document.write( "you are given that the number of the bacteria is increasing at the rate of 5% per hour.\r<BR>\n" );
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document.write( "your time period is therefore in hours, so t represents the number of hours.<BR>\n" );
document.write( "your rate of growth per hour is equal to 5% / 100 = .05, so r = .05.\r<BR>\n" );
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document.write( "the formula becomes f = p * (1 + .05) ^ t\r<BR>\n" );
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document.write( "since 400 bacteria are initially present, then p = 400.\r<BR>\n" );
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document.write( "the formula becomes f = 400 * (1 + .05) ^ t\r<BR>\n" );
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document.write( "after one hour, t = 1 and the formula becomes f = 400 * (1 +.05) ^ 1 = 400 * 1.05 = 420.\r<BR>\n" );
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document.write( "after 4 hours, t = 4 and the formula becomes f = 400 * (1 + .05) ^ 4 = 400 * 1.05^4 = 486.2025.\r<BR>\n" );
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document.write( "let y = f and x = t and you can graph this equation as shown below.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" src = \"http://theo.x10hosting.com/2018/101601.jpg\" alt=\"$$$\" >\r<BR>\n" );
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