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प्रश्न
Let the p.m.f. of a random variable X be P(x) = `(3 - x)/10`, for x = −1, 0, 1, 2 = 0, otherwise Then E(x) is ______
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p = probability that bomb will hit the target = `square`
∴ q = 1 - p = `square`
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∴ P(X = x) = `""^"n""C"_x"P"^x"q"^("n" - x) = square`
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Here, n = 4
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| 2 | 3 | 4 | 5 | |
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| 5 | (5, 3) | (5, 4) | (5, 5) |
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X 3 4 5 P(X = x) - Find the value of P(X < 5)
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