The probability mass function of a random variable is given to be for ; and zero elsewhere. Then the mean of the distribution is
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4 marks, −1StatisticsRandom variables and standard distributionsExpectation and varianceEasyabout 1 min
JNU SIS 2014 Question 15: Random variables and standard distributions
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The probability mass function of a random variable is given to be f(x) = x/15 for x = 1, 2, 3, 4, 5; and zero elsewhere. Then the mean of the distribution is (A) 3 (B) 5/2 (C) 11/3 (D) 15/2
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What this question tests
This question is on Expectation and variance, part of Random variables and standard distributions in Statistics.
The mean and spread of a random variable, and how they change under transformations and sums.
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