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Question
The probability distribution of a random variable X is given below:
| X | 0 | 1 | 2 | 3 |
| P(X) | k | `"k"/2` | `"k"/4` | `"k"/8` |
Find P(X ≤ 2) + P (X > 2)
Solution
P(X ≤ 2) + P (X > 2) = `14/15 + 1/15`
= `(14 + 1)/15`
= `15/15`
= 1.
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