If a fossil contains 50% of the amount of carbon that a living animal contains, how many half lives have passed while it decayed? How old is the fossil? (half lives x 5730)
The currently accepted value for the half-life of 14C is 5,730 years. This means that after 5,730 years, only half of the initial 14C will remain; a quarter will remain after 11,460 years; an eighth after 17,190 years; and so on.
