document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=134084>Question 134084</A>: <I><SPAN STYLE=\"word-break: break-all;\"> If 100 grams of a radioactive material diminish to 80 grams in 2 years, find the half life of the substance: If 100 grams of a radioactive material diminish to 80 grams in 2 years, find the half life of the substance\r<BR>\n" );
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document.write( "The answer is actually 6.21 years how do I get this answer? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #98051 by </B><A HREF=/tutors/aboutme.mpl?userid=Ganesha><B>Ganesha(13)</B></A><img src=\"/images/stars/stars-06.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Ganesha><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=98051\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> decay = .8 in 2year.\r<BR>\n" );
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document.write( "Solve  for .8^(x/2) =.5<BR>\n" );
document.write( "x/2 = log.5/log.8<BR>\n" );
document.write( "x=2log.5/log.8 =6.212567439 </SPAN>\n" );
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