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प्रश्न
A random variable X has the following probability distribution
| X | 2 | 3 | 4 |
| P(x) | 0.3 | 0.4 | 0.3 |
Then the variance of this distribution is
पर्याय
0.6
0.7
0.77
0.66
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उत्तर
0.6
संबंधित प्रश्न
State the following are not the probability distributions of a random variable. Give reasons for your answer.
| Z | 3 | 2 | 1 | 0 | -1 |
| P(Z) | 0.3 | 0.2 | 0.4 | 0.1 | 0.05 |
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Find the probability distribution of number of heads in four tosses of a coin.
A random variable X has the following probability distribution.
| X | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 |
| P(X) | 0 | k | 2k | 2k | 3k | k2 |
2k2 |
7k2 + k |
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(i) k
(ii) P (X < 3)
(iii) P (X > 6)
(iv) P (0 < X < 3)
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| P(x) | -0.2 | 1 | 0.2 |
The p.m.f. of a random variable X is
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Solve the following problem :
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Solve the following problem :
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Solve the following problem :
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| x | 1 | 2 | 3 | 4 | 5 | 6 | 7 |
| P(x) | k | 2k | 2k | 3k | k2 | 2k2 | 7k2 + k |
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- k
- P(X < 3)
- P(X > 4)
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