document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=62855>Question 62855</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/0495012661/algebrahomeworkh>college algebra</A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> This is a carbon decay question that I haven't encounted yet.  Can anyone give me a hand here?  Thanks!\r<BR>\n" );
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document.write( "Question:  Only 25% of the carbon-14 in a wooden bowl remains.  How old is the bowl?\r<BR>\n" );
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document.write( "Thanks for your help! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #43672 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=43672\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> This is a carbon decay question that I haven't encounted yet. Can anyone give me a hand here? Thanks!<BR>\n" );
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document.write( "Question: Only 25% of the carbon-14 in a wooden bowl remains. How old is the bowl?<BR>\n" );
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document.write( "The Half-life formula: A = Ao*.5^(t/h)<BR>\n" );
document.write( "Where:<BR>\n" );
document.write( "A = resulting amt; 25% here<BR>\n" );
document.write( "Ao= Initial amt; 1 here<BR>\n" );
document.write( "t = time (in years here)<BR>\n" );
document.write( "h = half life, (carbon 14 half-life given as 5730 yrs)<BR>\n" );
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document.write( ".25 = 1 * .5^(t/5730)<BR>\n" );
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document.write( "Use the log equiv of exponent:<BR>\n" );
document.write( "ln(.25) = (t/5730) * ln(.5)<BR>\n" );
document.write( "-1.38629 = (t/5730) * -.693147<BR>\n" );
document.write( "-1.38629 = -.693147t/5730<BR>\n" );
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document.write( "Get rid of denominator, mult equation by 5730<BR>\n" );
document.write( "-1.3829*5730 = -.693147t<BR>\n" );
document.write( "-7943.466689 = -.693147t<BR>\n" );
document.write( "t = -7943.466689/-.693147<BR>\n" );
document.write( "t = 11,460 yrs<BR>\n" );
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document.write( "Check:<BR>\n" );
document.write( "A = 1*.5^(11460/5740); using a good calc<BR>\n" );
document.write( "A = .25<BR>\n" );
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