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Question
Choose the correct alternative:
Let X be random variable with probability density function
`f(x) = {(2/x^3, x ≥ 1),(0, x < 1):}`
Which of the following statement is correct?
Options
Both mean and variance exist
Mean exists but variance does not exist
Both mean and variance do not exist
Variance exists but mean does not exist.
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Solution
Mean exists but variance does not exist
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