document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1100281>Question 1100281</A>: <I><SPAN STYLE=\"word-break: break-all;\"> In&#8203; 2012, the population of a city was 5.72 million. The exponential growth rate was 3.79 per year.<BR>\n" );
document.write( "&#8203;a) Find the exponential growth function.<BR>\n" );
document.write( "&#8203;b) Estimate the population of the city in 2018.<BR>\n" );
document.write( "&#8203;c) When will the population of the city be 88 &#8203;million?<BR>\n" );
document.write( "&#8203;d) Find the doubling time.\r<BR>\n" );
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document.write( "This one's also a big one and it is pretty hard. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #714768 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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=714768\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> In&#8203; 2012, the population of a city was 5.72 million. The exponential growth rate was 3.79 per year.<BR>\n" );
document.write( "&#8203;a) Find the exponential growth function.<BR>\n" );
document.write( "A(t) = 5.72*3.79^t<BR>\n" );
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document.write( "&#8203;b) Estimate the population of the city in 2018.<BR>\n" );
document.write( "A(6) = 5.72*2.79^6<BR>\n" );
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document.write( "&#8203;c) When will the population of the city be 88 &#8203;million?<BR>\n" );
document.write( "Solve for \"t\"::<BR>\n" );
document.write( "88 = 5.72*2.79^t<BR>\n" );
document.write( "2.79^t = 15.38<BR>\n" );
document.write( "t = log(15.38)/(log(2.79)) = 2.66 years<BR>\n" );
document.write( "Ans:: 2018 + 2.66 yrs = 2021<BR>\n" );
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document.write( "&#8203;d) Find the doubling time.<BR>\n" );
document.write( "2*5.72 = 5.72*3.79^t<BR>\n" );
document.write( "3.79^t = 2<BR>\n" );
document.write( "t = log(2)/log(3.79)<BR>\n" );
document.write( "t = 0.52<BR>\n" );
document.write( "Ans:: 2018 + 0.52(12 mts) = 2018 and 6 mts<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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document.write( "This one's also a big one and it is pretty hard. <BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );