# An animal dies in the forest. How long will it be until only #7/8# of the original amount of Carbon 14 remains?

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Recall that the half life of Carbon 14 is 5568 years. Round to the nearest year.

*NOTE: The half-life is incorrect. It is 5730 years.*

- Truong-Son

Recall that the half life of Carbon 14 is 5568 years. Round to the nearest year.

*NOTE: The half-life is incorrect. It is 5730 years.
- Truong-Son*

##### 1 Answer

#### Explanation:

All thanks to Truong-Son Nguyen, aka his method!

We use one of the radioactive decay equation, which states that

#[A]# is the amount of substance right now

#[A]_0# is the original amount

#-k# is the decay constant, and it is negative because the system experiences decay

#t# is the time in years

We also have half-life,

From the original equation, we have

Therefore, the decay constant becomes,

And so, we get,