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Question
Determine whether each of the following is a probability distribution. Give reasons for your answer.
| x | 0 | 1 | 2 |
| P(x) | 0.3 | 0.4 | 0.2 |
Solution
Here, pi > 0, `AA` i = 1, 2, 3
Now consider,
\[\sum\limits_{i=1}^{3} \text{P}_i\] = 0.3 + 0.4 + 0.2 = 0.9 ≠ 1
∴ Given distribution is not a probability distribution.
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