Question

If the p.m.f of a r. v. X is

P(x) = `c/x^3`, for x = 1, 2, 3

        = 0, otherwise

then E(X) = ______.

Options

• `216/251`

• `294/251`

• `297/294`

• `294/297`

Answer 1

If the p.m.f of a r. v. X is

P(x) = `c/x^3`, for x = 1, 2, 3

        = 0, otherwise

then E(X) = `bb(294/251)`.