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प्रश्न
Determine whether each of the following is a probability distribution. Give reasons for your answer.
| x | 0 | 1 | 2 |
| P(x) | 0.4 | 0.4 | 0.2 |
उत्तर
Here, P(x) > 0 for all values of x
Now, consider,
∴ Given distribution is a probability distribution.
संबंधित प्रश्न
State the following are not the probability distributions of a random variable. Give reasons for your answer.
| X | 0 | 1 | 2 |
| P (X) | 0.4 | 0.4 | 0.2 |
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(i) all will bear ‘X’ mark.
(ii) not more than 2 will bear ‘Y’ mark.
(iii) at least one ball will bear ‘Y’ mark
(iv) the number of balls with ‘X’ mark and ‘Y’ mark will be equal.
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Find the mean and standard deviation of each of the following probability distribution :
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| x = x | 0 | 1 | 2 | 3 | 7 | |||
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