[tex]A=A_0\cdot(\frac{1}{2})^{\frac{t}{h}}[/tex]
For the given situation:
[tex]\begin{gathered} A_0=24g \\ h=1430 \\ t=500 \\ \\ A=24(\frac{1}{2})^{\frac{500}{1430}} \\ \\ A=24(\frac{1}{2})^{\frac{50}{143}} \\ \\ A\approx18.83g \end{gathered}[/tex]
Then, after 500 years there will be approxiomately 18.83 grams of the radioactive isotope
