document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=190670>Question 190670</A>: <I><SPAN STYLE=\"word-break: break-all;\"> In a town whose population is 3500, a disease creates an epidemic. The number of people N infected after t days after the disease has begun, is given by the function\r<BR>\n" );
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document.write( "N  = 3500/1 + 19.9e^-0.6t\r<BR>\n" );
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document.write( "Find the number of people infected after 15 days. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #143150 by </B><A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><B>jim_thompson5910(35256)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><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=143150\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=N=%283500%29%2F%281%2B19.9e%5E%28-0.6t%29%29 ALIGN=MIDDLE  ALT=\"N=%283500%29%2F%281%2B19.9e%5E%28-0.6t%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > Start with the given equation.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=N=%283500%29%2F%281%2B19.9e%5E%28-0.6%2815%29%29%29 ALIGN=MIDDLE  ALT=\"N=%283500%29%2F%281%2B19.9e%5E%28-0.6%2815%29%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > Plug in <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t=15 ALIGN=MIDDLE  ALT=\"t=15\"   DISABLED_style= \"max-width:90%; height:auto;\" >.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=N=%283500%29%2F%281%2B19.9e%5E%28-9%29%29 ALIGN=MIDDLE  ALT=\"N=%283500%29%2F%281%2B19.9e%5E%28-9%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > Multiply -0.6 and 15 to get -9\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=N=%283500%29%2F%281%2B19.9%280.000123%29%29 ALIGN=MIDDLE  ALT=\"N=%283500%29%2F%281%2B19.9%280.000123%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > Raise \"e\" to the negative 9th power to get 0.000123\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=N=%283500%29%2F%281%2B0.00245%29 ALIGN=MIDDLE  ALT=\"N=%283500%29%2F%281%2B0.00245%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > Multiply 19.9 and 0.000123 to get 0.00245\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=N=%283500%29%2F%281.00245%29 ALIGN=MIDDLE  ALT=\"N=%283500%29%2F%281.00245%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > Add 1 to 0.00245 to get 1.00245\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=N=3491.445 ALIGN=MIDDLE  ALT=\"N=3491.445\"   DISABLED_style= \"max-width:90%; height:auto;\" > Divide\r<BR>\n" );
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document.write( "So rounding to the nearest whole number (since 0.445 of a person doesn't make sense), we get 3,491 people. \r<BR>\n" );
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document.write( "So after 15 days, about 3,491 people are infected. </SPAN>\n" );
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