Answer:
Step-by-step explanation:
Decay of carbon - 14 is exponential in nature . It decays as follows .
[tex]N=N_0e^{-\lambda t}[/tex] λ is called decay constant .
λ = .693 / T where T is half life .
Half life of carbon-14 is 5700 years
λ = .693 / T
= .693 / 5700
= 12.158 x 10⁻⁵ year⁻¹
[tex]N=N_0e^{-\lambda t}[/tex]
N = .71 N₀
[tex].71 N_0 =N_0e^{-\lambda t}[/tex]
[tex].71 =e^{-\lambda t}[/tex]
Taking ln on both sides
ln .71 = - λ t
ln .71 = - 12.158 x 10⁻⁵ t
-0.3425 = - 12.158 x 10⁻⁵ t
t = .3425 / 12.158 x 10⁻⁵
2817 years .