The carbon buried in a peat bed has about 12.5% of the Carbon-14 of modern wood. What is the age of the peat bed? Explain?

Answer 1

half life of carbon 14 is about 5730 years

.125 = (1/2)^n where n is the number of half lives
log .125 = n log .5
n = 3 half lives

3 * 5730 = 17,190 years old