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Question
The cumulative distribution function of a discrete random variable is given by
F(x) = `{{:(0, "for" - oo < x < 0),(1/2, "for" 0 ≤ x < 1),(3/5, "for" 1 ≤ x < 2),(4/5, "for" 2 ≤ x < 4),(9/5, "for" 3 ≤ x < 4),(1, "for" ≤ x < oo):}`
Find P(X ≥ 2)
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Solution
P(X ≥ 2) = P(X = 2) + P(X = 3) + P(X = 4)
= `1/5 + 1/10 + 1/10`
= `4/10`
= `2/5`
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