document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1006816>Question 1006816</A>: <I><SPAN STYLE=\"word-break: break-all;\"> how long will it take a sample of radioactive substance to decay to half of its original amount if it decays according to the function a(t) = 200e^-.144(t) Where t is the time in years? Round your answer to the nearest hundredth year. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #622882 by </B><A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><B>josgarithmetic(39618)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><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=622882\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Show the function this way:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a%28t%29=200e%5E%28-.144%28t%29%29 ALIGN=MIDDLE  ALT=\"a%28t%29=200e%5E%28-.144%28t%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "To find half-life:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1%2Ae%5E%28-0.144t%29=%281%2F2%29 ALIGN=MIDDLE  ALT=\"1%2Ae%5E%28-0.144t%29=%281%2F2%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Take natural log of both sides and solve for t. </SPAN>\n" );
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