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प्रश्न
Find mean for the following probability distribution.
| X | 0 | 1 | 2 | 3 |
| P(X = x) | `1/6` | `1/3` | `1/3` | `1/6` |
उत्तर
Mean of the given distribution is
E(X) = `sumx_"i" "P"(x_"i")`
= `0(1/6) + 1(1/3) + 2(1/3) + 3(1/6)`
= `0 + 1/3 + 2/3 + 1/2`
= `3/2`
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