# Carbon-14 is a radioactive isotope with a half-life of 5,730 years. How much carbon-14 would remain in a sample that is 11,460 years old?

$\frac{1}{4}$
$11460 = 2 \times 5730$
$11460$ years is $2$ half-lives.
By the first half-life, the amount of $\text{C} 14$ would be half the original amount.
By the second half-life, the amount of $\text{C} 14$ would have halved again, resulting in a quarter of the original amount of $\text{C} 14$.