The following table shows the probability distribution for a discrete random variable. X 12 15 17 20 22 24 25 30 P (X) 0.07 0.21 0.17 0.25 0.05 0.04 0.13 0.08 What is the mean of this discrete random variable? (That is, what is E (X), the expected value of X?) A. 20 B. 19.59 C. 20.625 D. 21

Question

Mathematics

Beau

27 April, 04:42

The following table shows the probability distribution for a discrete random variable. X 12 15 17 20 22 24 25 30 P (X) 0.07 0.21 0.17 0.25 0.05 0.04 0.13 0.08 What is the mean of this discrete random variable? (That is, what is E (X), the expected value of X?) A. 20 B. 19.59 C. 20.625 D. 21

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Answers (1)

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Leonidas Payne · Answer 1

The mean of this discrete random variable can be calculated by finding for the summation of the weighted average:

Mean = Summation (Xi * P (Xi))

Therefore,

Mean = 12 (0.07) + 15 (0.21) + 17 (0.17) + 20 (0.25) + 22 (0.05) + 24 (0.04) + 25 (0.13) + 30 (0.08)

Mean = 19.59

Therefore the answer is letter B. 19.59