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प्रश्न
If the probability distribution of a random variable X is given by Write the value of k.
| X = xi : | 1 | 2 | 3 | 4 |
| P (X = xi) : | 2k | 4k | 3k | k |
उत्तर
We know that the sum of probabilities in a probability distribution is always 1.
∴ P (X = 1) + P (X = 2) + P (X = 3) + P (X = 4) = 1
\[\Rightarrow 2k + 4k + 3k + k = 1\]
\[ \Rightarrow 10k = 1\]
\[ \Rightarrow k = \frac{1}{10} = 0 . 1\]
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`P(X=x)=""^n"C"_x p^x q^(n-x)= ""^4"C"_x (0.1)^x (0.9)^(4 - x)`
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∴ P[X ≤ 1] = `square`
