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Question
The probability distribution function of a discrete random variable X is
f(x) = `{{:(2k",", x = 1),(3k",", x = 3),(4k",", x = 5),(0",", "otherwise"):}`
where k is some constant. Find P(X > 2)
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Solution
P(x > 1) = P(x = 3) + P(x = 5)
= 3k + 4k = 7k
= `7(1/9)`
= `7/9`
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