Suppose that X is a discrete random variable with the probability mass function Given by: p(x) = i/15 where i = 1, 2, 3, 4, 5. Determine the mean E(x) Determine Variance

nSuppose that X is a discrete random variable with the probability mass function
n Given by: p(x) = i/15 where i = 1, 2, 3, 4, 5.
nDetermine the mean E(x)
nDetermine Variance Var(x)

[Steven Lord]

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[Torsten]

Just use the definitions of E(X) and Var(X):

E(X)   = sum_{i=1}^{i=5} i * p(X = i)
Var(X) = sum_{i=1}^{i=5} (i - E(X))^2 * p(X = i)