document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=769161>Question 769161</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I don't know how to solve this and I can't find anything in my text for this...help please =/\r<BR>\n" );
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document.write( "The weight in kilograms,W, of a female African elephant at age t years is given by W(t)=2600(1-0.51e^-0.075t). Estimate the age, to the nearest year, of an adult female African elephant weighing 1800 kilograms. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #468695 by </B><A HREF=/tutors/aboutme.mpl?userid=Cromlix><B>Cromlix(4381)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Cromlix><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=Cromlix><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=468695\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> W(t) = 2600(1 - 0.51e^-0.075t)<BR>\n" );
document.write( "1800 = 2600(1 - 0.51e^-0.075t<BR>\n" );
document.write( "1800/2600 = 1 - 0.51e^-0.075t<BR>\n" );
document.write( "1800/2600 - 1 = -0.51e^-0.075t<BR>\n" );
document.write( "(1800/2600 - 1)/-0.51 = e^-0.075t<BR>\n" );
document.write( "0.6033 = e^-0.075t<BR>\n" );
document.write( "ln 0.6033 = -0.075t ln e<BR>\n" );
document.write( "(ln e = 1)<BR>\n" );
document.write( "ln 0.6033/-0.075 = t<BR>\n" );
document.write( "t = 6.7 years<BR>\n" );
document.write( "Hope this helps.<BR>\n" );
document.write( ":-) </SPAN>\n" );
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