Question

If the half-life of carbon-14 is 5730 years, how old is a mummy having only 30% of the normal amount of carbon-14?

Answer 1

17190 years.

Explanation:

The half-life of carbon-14 is

5730 years.

Therefore, after1 half-life there is 50%=12 of the original amount left.2half-lives there is 25%=14of the original amount left.3 half-lives there is 12.5%=18 of the original amount left.

1−78=18

So, your answer would be the time it takes for carbon-14 to elapse 3 half-lives.

5730⋅3=17190