<PRE><B>Question 444717</B>
A fossilized leaf contains 70% of its normal amount of carbon 14. How old is the fossil to the nearest year? Use 5600 years as the half life of carbon 14.
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Equation:
0.7*Ao = Ao*(1/2)^(t/5600)
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(1/2)^(t/5600) = 0.7
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Take the log of both sides to get:
(t/5600)*log(1/2) = log(0.7)
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(t/5600) = log(0.7)/log(1/2) = 0.5146
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t = 5600*0.5146
t = 2881.61 yrs.
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Cheers,
Stan H.
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