document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=81409>Question 81409</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/0534492770/algebrahomeworkh>Precalculus</A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> the frog population in a small pond grows exponentially. The current population is 85 frogs, and the relative growth rate is 18% per year. \r<BR>\n" );
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document.write( "a. find function that models the population after t years. <BR>\n" );
document.write( "b. find the projected population after 3 years. <BR>\n" );
document.write( "c. find the number of years required for the frog population to reach 600.  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #58310 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=58310\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> the frog population in a small pond grows exponentially. The current population is 85 frogs, and the relative growth rate is 18% per year. <BR>\n" );
document.write( "a. find function that models the population after t years.<BR>\n" );
document.write( "A(t) = A(0)(1.18)^t<BR>\n" );
document.write( "A(t) = 85(1.18)^t<BR>\n" );
document.write( "---------- <BR>\n" );
document.write( "b. find the projected population after 3 years.<BR>\n" );
document.write( "A(3) = 85(1.18)^3<BR>\n" );
document.write( "A(3)= 139.65 frogs<BR>\n" );
document.write( "Rounding down: 139 frogs<BR>\n" );
document.write( "-------------------- <BR>\n" );
document.write( "c. find the number of years required for the frog population to reach 600.<BR>\n" );
document.write( "600 = 85(1.18)^t<BR>\n" );
document.write( "7.0588=1.18^t<BR>\n" );
document.write( "Take the log of both sides to ge:<BR>\n" );
document.write( "t=[log7.0588]/[log1.18]<BR>\n" );
document.write( "t=11.81 years<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H. <BR>\n" );
document.write( " </SPAN>\n" );
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