document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=378592>Question 378592</A>: <I><SPAN STYLE=\"word-break: break-all;\"> This problem is about Radioactive decay...I am having a hard time solving the problem below..Any help will be appreciated.  Thank you..Could you show me the steps please?\r<BR>\n" );
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document.write( "the bones of a math professor contain 98% of the original amount of carbon 14 (decay rate =0.012% per year) how long ago did he die? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #268905 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=268905\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> the bones of a math professor contain 98% of the original amount of carbon 14 (decay rate =0.012% per year) how long ago did he die?<BR>\n" );
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document.write( "Note 0.012% = 0.012/100 = 0.00012<BR>\n" );
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document.write( "A(t) = Ao(1-0.00012)^t<BR>\n" );
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document.write( "0.98*Ao = Ao(0.999880)^t<BR>\n" );
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document.write( "0.999880^t = 0.98<BR>\n" );
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document.write( "Take the log to get:<BR>\n" );
document.write( "t*log0.999880 = log0.98<BR>\n" );
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document.write( "t = [log0.98]/[log0.999880]<BR>\n" );
document.write( "t = 168.35 years<BR>\n" );
document.write( "Round up to He died 168.35 years ago.<BR>\n" );
document.write( "=========================================<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
document.write( " </SPAN>\n" );
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