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प्रश्न
If a d.r.v. X takes values 0, 1, 2, 3, … with probability P(X = x) = k(x + 1) × 5–x, where k is a constant, then P(X = 0) = ______
विकल्प
`7/25`
`16/25`
`18/25`
`19/25`
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उत्तर
`16/25`
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