document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=471331>Question 471331</A>: <I><SPAN STYLE=\"word-break: break-all;\"> an artifact was found and tested for its carbon-14 content.  If 81% of the original carbon-14 was still present, what is it probable age(to the nearest 100yrs)? use that carbon-14 has a half-life of 5730 yrs. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #323268 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=323268\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> an artifact was found and tested for its carbon-14 content.<BR>\n" );
document.write( " If 81% of the original carbon-14 was still present, what is it probable age(to the nearest 100yrs)? <BR>\n" );
document.write( "use that carbon-14 has a half-life of 5730 yrs.<BR>\n" );
document.write( ":<BR>\n" );
document.write( "The half life formula: A = Ao*2^(-t/h)<BR>\n" );
document.write( "Where<BR>\n" );
document.write( "A = resulting amt after t yrs<BR>\n" );
document.write( "Ao = initial amt<BR>\n" );
document.write( "t = time in yrs<BR>\n" );
document.write( "h = half-life of substance<BR>\n" );
document.write( ":<BR>\n" );
document.write( "When we are dealing with percent we can  use the initial amt of 100<BR>\n" );
document.write( ":<BR>\n" );
document.write( "100*2^(-t/5730) = 81<BR>\n" );
document.write( "2^(-t/5730) = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=81%2F100 ALIGN=MIDDLE  ALT=\"81%2F100\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "2^(-t/5730) = .81<BR>\n" );
document.write( "find the nat log of both sides<BR>\n" );
document.write( "ln(2^(-t/5730)) = ln(81)<BR>\n" );
document.write( "log equiv of exponents<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(81)<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%2881%29%2Fln%282%29 ALIGN=MIDDLE  ALT=\"ln%2881%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;\" > = -.304<BR>\n" );
document.write( "multiply both sides by -5730, results<BR>\n" );
document.write( "t = 1,742 yrs\r<BR>\n" );
document.write( "\n" );
document.write( " </SPAN>\n" );
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