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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` |
Determine P(X ≤ 2) and P(X > 2)
Solution
P(X ≤ 2) = P(X = 0) + P(X = 1) + P(X = 2)
= `"k" + "k"/2 + "k"/4`
= `(7"k")/4`
= `7/4 xx 8/15`
= `14/15`
And P(X > 2) = P(X = 3)
= `"k"/8`
= `1/8 xx 8/15`
= `1/15`
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