document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1130958>Question 1130958</A>: <I><SPAN STYLE=\"word-break: break-all;\"> If anyone can help me solve this, I would be so appreciative.  This is day two of trying to solve this successfully.  Thanks.\r<BR>\n" );
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document.write( "The amount of&#8203; carbon-14 present in animal bones after t years is given by &#8203;P(t)<BR>\n" );
document.write( "=P0e superscript&#8722;0.00012t. A bone has lost 11&#8203;% of its&#8203; carbon-14. How old is the&#8203; bone?<BR>\n" );
document.write( "The bone is ____________years old.<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #747562 by </B><A HREF=/tutors/aboutme.mpl?userid=greenestamps><B>greenestamps(13200)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=greenestamps><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=greenestamps><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=747562\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <br><BR>\n" );
document.write( "The bone has lost 11% of its Carbon-14, so the percent remaining is 89%; the fraction remaining is 0.89.  The fraction remaining is the current amount, P(t), divided by the original amount, P(0).  So<br><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=P%28t%29%2FP%280%29+=+0.89 ALIGN=MIDDLE  ALT=\"P%28t%29%2FP%280%29+=+0.89\"   DISABLED_style= \"max-width:90%; height:auto;\" ><br><BR>\n" );
document.write( "The given formula for the amount remaining is<br><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=P%28t%29+=+P%280%29%2Ae%5E%28-0.00012t%29 ALIGN=MIDDLE  ALT=\"P%28t%29+=+P%280%29%2Ae%5E%28-0.00012t%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><br><BR>\n" );
document.write( "That formula is equivalent to<br><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=P%28t%29%2FP%280%29+=+e%5E%28-0.00012t%29 ALIGN=MIDDLE  ALT=\"P%28t%29%2FP%280%29+=+e%5E%28-0.00012t%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><br><BR>\n" );
document.write( "So we want to solve for the number of years t in the equation<br><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=e%5E%28-0.00012t%29+=+0.89 ALIGN=MIDDLE  ALT=\"e%5E%28-0.00012t%29+=+0.89\"   DISABLED_style= \"max-width:90%; height:auto;\" ><br><BR>\n" );
document.write( "Since the exponential is base e, take the natural log of both sides of the equation:<br><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-0.00012t+=+ln%280.89%29 ALIGN=MIDDLE  ALT=\"-0.00012t+=+ln%280.89%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><br><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t+=+ln%280.89%29%2F-0.00012%29 ALIGN=MIDDLE  ALT=\"t+=+ln%280.89%29%2F-0.00012%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > = 971 years to the nearest whole number </SPAN>\n" );
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