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Question
Solve the following problem :
Following is the probability distribution of a r.v.X.
| X | – 3 | – 2 | –1 | 0 | 1 | 2 | 3 |
| P(X = x) | 0.05 | 0.1 | 0.15 | 0.20 | 0.25 | 0.15 | 0.1 |
Find the probability that X is positive.
Solution
P(X is positive)
= P(X = 1 or X = 2 or X = 3)
= P(X = 1) + P(X = 2) + P(X = 3)
= 0.25 + 0.15 + 0.10
= 0.50
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