Correct Question:
A mammoth skeleton has a carbon-14 content of 12.50% of that found in living organisms. When did the mammoth live?
Answer:
17,190 years ago.
Explanation:
The carbon-14 is a carbon isotope that has a half-life of 5730 years. It means that the mass of carbon-14 decreases by half every 5730 years. If we call the initial mass as M and the final mas as m:
m = M/2ⁿ
Where n is the amount of half-live that had past. Thus, in this case, the mass of the skeleton is the final mass, and the mass founded in the living organisms the initial mass, so:
m = 0.1250M, and
0.1250M = M/2ⁿ
2ⁿ = M/0.1250M
2ⁿ = 1/0.1250
2ⁿ = 8
2ⁿ = 2³
n = 3
So it had past 3 half-live or
3*5730 = 17,190 years.
So the mammoth lived 17,190 years ago.
