<PRE><B>Question 442233</B>
Human hair from a grave in Africa proved to have only 85% of the carbon 14 of living tissue. When was the body buried? The half life of carbon 14 is 5730 years. How many years ago was the body buried?
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A(t) = Ao*(1/2)^(t/5730)
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0.85*A0 = Ao(1/2)^(t/5730)
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(1/2)^(t/5730) = 0.85
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(t/5730)*ln(1/2) = ln(0.85)
t/5730 = ln(0.85)/ln(1/2) = 0.2345
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t = 5730*0.2345
t = 1343.49 years
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Cheers,
Stan H.
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