6. Let X represent the number of times a customer visits a grocery store in a one-week period. Assume this is the probability distribution of X: x 0 1 2 3 P(X = x) 0.12 0.42 0.38 0.08 (a) What is the probability that a randomly selected customer visits a grocery store at least once in a one-week period? (b) Find the expected value of X, the mean number of times a customer visits the store in a one-week period. (c) Calculate the standard deviation for the random variable X. Round your answer to four decimal places.
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To find the probability that a customer visits the store at least once, we need to add the probabilities of visiting once, twice, or three times. P(X ≥ 1) = P(X = 1) + P(X = 2) + P(X = 3) P(X ≥ 1) = 0.42 + 0.38 + 0.08 P(X ≥ 1) = 0.88 Therefore, the probability Show more…
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