Question

Suppose that the probabilities of a customer purchasing​ 0, 1, or 2 books at a book store are 0.4​, 0.2​, and 0.4​, respectively. What is the expected number of books a customer will​ purchase?

Answer 1

Expected number of books = 1.0

Explanation:

Expected number of books, E(x) = ∑xp(x)

∑ = Summation

x = books

p(x) = probability of purchasing a book

E(x) = (0*0.4) + (1*0.2) + (2*0.4)

E(x) = 0 + 0.2 + 0.8 = 1.0