Question

An artifact contains one-fourth as much carbon-14 as the atmosphere. how old is the artifact

Answer 1

Answer;

= 11,460 years

Explanation;

• The half life of Carbon-14 is 5,730 years . Half life is the time taken by a radioactive material to decay by half of its original mass.  Therefore, it  would take a time of 5730 years for a sample of 100 g of carbon-14 to decay to 50 grams

The initial amount of carbon-14 in this case was 1 whole; thus;

1 → 1/2 →1/4

To contain 1/4 of the value, 2 half-lives have passed.

But, 1 half life = 5,730 years

Therefore; The artifact is is therefore: 2 x 5,730

         = 11,460 years

Answer 2

The half life of Carbon-14 is 5,730 years
To contain 1/4 of the value, 2 half-lives must have passed.
The artifact is: 2 x 5,730
= 11,460 years older than the atmosphere.