P\(x=x_1\)=\(\Large\frac{1}{10,000}\)
P\(x=x_2\)=\(\Large\frac{1}{10,000}\)
P\(x=x_3\)=\(\Large\frac{3}{10,000}\)
\(E(X)=\Large\;3000\times\;\frac{1}{10,000}\;+2000\times\;\frac{1}{10,000}\;+500\times\;\frac{1}{10,000}\)
=\(\Large\frac{65}{100}\)
=\(0.65\)