document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=633093>Question 633093</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Near Three Rivers, NM, there is an archaeological site containing petroglyphs. In 1998, archaeologists found that the amount of carbon-14 in the petroglyphs was 88.5%. Determine the approximate age of the petroglyphs. Show the carbon-14 dating model for the age of the petroglyphs and define variables. Explain how you found your answer. There are directions for how to type math characters in the Resource Center that will show you show to enter exponents and fractions.  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #398782 by </B><A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><B>ankor@dixie-net.com(22740)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><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=ankor@dixie-net.com><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=398782\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> In 1998, archaeologists found that the amount of carbon-14 in the petroglyphs<BR>\n" );
document.write( " was 88.5%. <BR>\n" );
document.write( " Determine the approximate age of the petroglyphs. <BR>\n" );
document.write( " Show the carbon-14 dating model for the age of the petroglyphs<BR>\n" );
document.write( ":<BR>\n" );
document.write( "Radio active decay formula<BR>\n" );
document.write( "A = Ao(2^(-t/h), where:<BR>\n" );
document.write( "A = remaining amt after t years<BR>\n" );
document.write( "Ao = initial amt t=0<BR>\n" );
document.write( "t = time in yrs<BR>\n" );
document.write( "h = half-life of substance<BR>\n" );
document.write( "t = time of decay<BR>\n" );
document.write( ":<BR>\n" );
document.write( "A = .885<BR>\n" );
document.write( "Ao = 1<BR>\n" );
document.write( "h = 5730, the half life of carbon-14<BR>\n" );
document.write( ":<BR>\n" );
document.write( "1*2^(-t/5730) = .885<BR>\n" );
document.write( "using nat logs<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-t%2F5730 ALIGN=MIDDLE  ALT=\"-t%2F5730\"   DISABLED_style= \"max-width:90%; height:auto;\" >*ln(2) = ln(.885)<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-t%2F5730 ALIGN=MIDDLE  ALT=\"-t%2F5730\"   DISABLED_style= \"max-width:90%; height:auto;\" > = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=ln%28.885%29%2Fln%282%29 ALIGN=MIDDLE  ALT=\"ln%28.885%29%2Fln%282%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-t%2F5730 ALIGN=MIDDLE  ALT=\"-t%2F5730\"   DISABLED_style= \"max-width:90%; height:auto;\" > = -.17625<BR>\n" );
document.write( "t = -5730 * -.17625<BR>\n" );
document.write( "t = 1010 years is the age of the petro-whatevers\r<BR>\n" );
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document.write( " </SPAN>\n" );
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