Question

The half-life of carbon 14 is 5730 years. if a 1 g sample of old carbon is 1/8 as radioactive as 1 g of a current sample, then the age of the old sample is about ___________years.

22,900

17,200

11,500

716

Answer 1

if I am correct, B. 17,200. I looked it up and this is what it said "b.) 17,200

if it takes 5730 years to be half then it takes 2*5730 years to be a quarter and 3*5730 years to be an eighth (2^3=8) so to get an 1/8 you need to half it 3 times and it takes 5730 years to half each time, thus 3*5730 ~ 17,200"

Answer 2

Thanks

Answer 3

No problem.