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Question
The probability function of a random variable X is given by
p(x) = `{{:(1/4",", "for" x = - 2),(1/4",", "for" x = 0),(1/2",", "for" x = 10),(0",", "elsewhere"):}`
Evaluate the following probabilities
P(0 ≤ X ≤ 10)
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Solution
| X | – 2 | 0 | 10 |
| P(X = x) | `1/4` | `1/4` | `1/2` |
P(0 ≤ X ≤ 10) = P(X = 0) + P(X = 10)
=`1/4 + 1/2`
= `(1 + 2)/4`
= `3/4`
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