<PRE><B>Question 599271</B>
Carbon 14 decays continously at the rate of 0.01245% per year. If 13% of the original carbon-14 remains in a specimen, estimate its age in years.---------------------------------------
A(t) = Ao*[1-0.0001245]^t
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0.13Ao = Ao*[1-0.001245]^t
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0.13 = 0.999875^t
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Take the ln of both sides:
t = ln(0.13)/ln(0.99875)
t = 1631 years
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Cheers,
Stan H.
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