document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=198180>Question 198180</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/9781567655513/algebrahomeworkh>Amsco Math B</A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> A=A 2^-t/5760\r<BR>\n" );
document.write( "\n" );
document.write( "A= amount of carbon 14 that a specimen contains<BR>\n" );
document.write( "A= original amount of carbon 14<BR>\n" );
document.write( "t=time in years<BR>\n" );
document.write( "5760= half life of carbon-14 <BR>\n" );
document.write( "A specimen that originally contained 120 milligrams of carbon-1 now contains 100 milligrams of this substance, what is the age of the specimen, to the nearest hundred years?    </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #148658 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=148658\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A(t) = Ao 2^(-t/5760) <BR>\n" );
document.write( "A= amount of carbon 14 that a specimen contains<BR>\n" );
document.write( "A= original amount of carbon 14<BR>\n" );
document.write( "t=time in years<BR>\n" );
document.write( "5760= half life of carbon-14<BR>\n" );
document.write( "---------------------------------------- <BR>\n" );
document.write( "A specimen that originally contained 120 milligrams of carbon-1 now contains 100 milligrams of this substance, what is the age of the specimen, to the nearest hundred years?<BR>\n" );
document.write( "---<BR>\n" );
document.write( "100 = 120*2^(-t/5760)<BR>\n" );
document.write( "(5/6) = 2^(-t/576)0<BR>\n" );
document.write( "Take the log to get:<BR>\n" );
document.write( "(-t/5760)log(2) = log(5/6)<BR>\n" );
document.write( "-t/5760 = -0.263034<BR>\n" );
document.write( "t = 1515.078 year<BR>\n" );
document.write( "t = 1500 years when rounded to the nearest 100<BR>\n" );
document.write( "====================<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "Stan H. <BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );