On a popular app, users rate hair salons as 1, 2, 3, 4, or 5 stars....

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On a popular app, users rate hair salons as 1, 2, 3, 4, or 5 stars. Suppose a rating is randomly selected from all the ratings on the app. Let X be the number of stars of the selected rating. Here is the probability distribution of X. Value x of X 1 2 3 4 5 P(X=x) 0.25 0.19 0.09 0.21 0.26 For parts (a) and (b) below, find the probability that the randomly selected hair salon rating has the described number of stars. (a) 4 or more: (b) Fewer than 3: Let X be a random variable with the following probability distribution. Value x of X P(X=x) 4 0.05 5 0.30 16 0.10 7 0.50 8 0.05 Complete the following. (If necessary, consult a list of formulas.) (a) Find the expectation E (X) of X. E (X) = (b) Find the variance Var () of X. Var (X) = On a popular app, users rate hair salons as 1, 2, 3, 4, or 5 stars. Suppose a rating is randomly selected from all the ratings on the app. Let X be the number of stars of the selected rating. Here is the probability distribution of X. Value x of X 1 2 3 4 5 P(X=x) 0.25 0.19 0.09 0.21 0.26 For parts (a) and (b) below, find the probability that the randomly selected hair salon rating has the described number of stars. (a) 4 or more: (b) Fewer than 3: Let X be a random variable with the following probability distribution. Value x of X P(X=x) 4 0.05 5 0.30 16 0.10 7 0.50 8 0.05 Complete the following. (If necessary, consult a list of formulas.) (a) Find the expectation E (X) of X. E (X) = (b) Find the variance Var () of X. Var (X) =