A geologist in South America discovers a bird skeleton that contains 80% of its original amount of C-14
We use formula
N0= initial amont of C-14 (at time t=0)
N= amount of C-14 at time t
t= time, in years
k= 0.0001
N is 80% of N0 that is
Divide both sides by N_o
Take ln on both sides
ln(0.8) = -0.0001t ln(e)
ln(0.8) = -0.0001t
Divide both sides by -0.001
t = 2231.435513
The age of the bird skeleton is 2231 years old