document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=982683>Question 982683</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A radio active isotope decays according to the exponential decay equation where t is in days. \r<BR>\n" );
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document.write( "Round to the thousandths place. \r<BR>\n" );
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document.write( "For the half life: The half life is the solution (t) of the equation : <BR>\n" );
document.write( "a/2=ae^&#8722;4.457t </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #603484 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=603484\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Hi there,<BR>\n" );
document.write( "a/2=ae^&#8722;4.457t<BR>\n" );
document.write( "Using a = 10 and a/2 = 5<BR>\n" );
document.write( "a/2=ae^&#8722;4.457t<BR>\n" );
document.write( "5 = 10 e^-4.457t<BR>\n" );
document.write( "5/10 = e^4.457t<BR>\n" );
document.write( "0.5 = e^-4.457t<BR>\n" );
document.write( "ln0.5 = -4.457t ln e (ln e = 1)<BR>\n" );
document.write( "ln 0.5 = -4.457t<BR>\n" );
document.write( "t = ln 0.5/-4.457<BR>\n" );
document.write( "t = 0.156 days<BR>\n" );
document.write( "Hope this helps:-) </SPAN>\n" );
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