document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=48241>Question 48241</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/0534373526/algebrahomeworkh>College Algebra</A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> The burial cloth of an Egyptian mummy is estimated to contain 59% of the carbon-14 it contained originally. How long ago was the mummy buried? (The half-life of carbon-14 is 5730 years.)\r<BR>\n" );
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document.write( "I got:<BR>\n" );
document.write( "m(t) = m0e^-(ln2/n)t<BR>\n" );
document.write( "0.59 = 1e^-(ln2/5730)t<BR>\n" );
document.write( "ln(0.59) = -(ln2/5730)t<BR>\n" );
document.write( "t = 5730(ln0.59)/ln2 = 4,362 years ago\r<BR>\n" );
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document.write( "Does this seem right?\r<BR>\n" );
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document.write( "Thanks for all your wonderful help! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #31908 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=31908\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Your formula certainly works and your answer is essentially<BR>\n" );
document.write( "correct.  I use a different formula for half-life problems.<BR>\n" );
document.write( "For what it is worth I get:\r<BR>\n" );
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document.write( "0.59A = A(1/2)^(t/5730)<BR>\n" );
document.write( "0.59 = (1/2)^(t/5730)<BR>\n" );
document.write( "ln0.59 = (t/5730)(ln0.5)<BR>\n" );
document.write( "t=5730[(ln0.59/ln0.5]<BR>\n" );
document.write( "t= 4361.75 yrs.\r<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
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