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The ratio of 14C12C in a piece of wood is 18 part that of atmosphere. If half life of 14C is 5730 years, the age of wood sample is years.
17190
14C decay is first order: NN0 = ( 12 )n, n = number of half-lives
18 = ( 12 )3 ⇒ n = 3
∴ age = 3 t1/2 = 3 5730 = 17190 years
Answer: 17190
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