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प्रश्न
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) = ______.
पर्याय
`216/251`
`294/251`
`297/294`
`294/297`
उत्तर
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)`.
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