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प्रश्न
A bag contains 1 red and 3 white balls. Find the probability distribution of the number of red balls if 2 balls are drawn at random from the bag one-by-one without replacement.
उत्तर
Let X be the random variable defined as the number of red balls.
Then X = 0, 1
P(X = 0) = `3/4 xx 2/3 = 6/12 = 1/2`
P(X = 1) = `1/4 xx 3/3 + 3/4 xx 1/3 = 6/12 = 1/2`
Probability Distribution Table:
| X | 0 | 1 |
| P(X) | `1/2` | `1/2` |
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