Chemistry

Problem

A mixture of

\text{Pu}^{239}

and

\text{Pu}^{240}

has a specific activity of

6 \times 10^9 \text{ dps per g sample}

. The half-lives of the isotopes are

2.44 \times 10^4 \text{ year}

and

6.58 \times 10^3 \text{ year}

respectively. Calculate the composition of mixture.