Problem 4 - Calculate the age of a fossil

If 12% of the initial amount of ¹⁴C in a sample remains, how much time has elapsed?

17,436 years

After approximately 17,436 years, 12% of the initial sample remains. Notice that we did not need to know how much ¹⁴C was contained in our original sample. We only needed to know that a certain percentage of it remained.

Our answer makes sense since 50% would remain after 5700 years, 25% would remain after 11,400 years, and 12.5% would remain after 17,100 years.

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