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Question
The probability distribution of a random variable X is given below:
| x | 0 | 1 | 2 | 3 |
| P(X) | k |
\[\frac{k}{2}\]
|
\[\frac{k}{4}\]
|
\[\frac{k}{8}\]
|
Find P(X ≤ 2) + P(X > 2) .
Solution
We have,
The probability distribution of a random variable X is given below:
| x | 0 | 1 | 2 | 3 |
| P(X) | k |
\[\frac{k}{2}\]
|
\[\frac{k}{4}\]
|
\[\frac{k}{8}\]
|
\[ P\left( X \leq 2 \right) + P\left( X > 2 \right)\]
\[ = \frac{14}{15} + \frac{1}{15} \left[ \text.........{ \text{ Using } } \left( ii \right) \right]\]
\[ = \frac{15}{15}\]
\[ = 1\]
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