Question

An anthropologist finds there is so little Carbon-14 remaining in a prehistoric bone that instruments cannot measure it. This means there is less than 0.2% of the amount of Carbon-14 the bones would have contained when the person was alive. How long ago did the person die? (The constant for Carbon-14 is 0.00012.)
Answer
13,411 years
22,491 years
45,020 years
51,788 years

Answer 1

N = I*e^(-kt)

N = I*e^(-0.00012t)

0.002I = I*e^(-0.00012t)

0.002 = e^(-0.00012t)

ln(0.002) = -0.00012t

ln(0.002)/(-0.00012) = t

51788.4008 = t

t = 51788.4008


which rounds to 51,788 years

Answer 2

Thanks ;)

Answer 3

you're welcome