Question

Suppose that the probabilities of a customer purchasing​ 0, 1, or 2 books at a book store are 0.20.2​, 0.20.2​, and 0.60.6​, respectively. what is the expected number of books a customer will​ purchase?

Answer 1

Form the sum of products of probability and number of books:

0.2×0 +0.2×1 +0.6×2 = 0 +.2 +1.2 = 1.4 books