Question

The probabilities that a customer selects 1, 2, 3, 4, or 5 items at a store are 0.32, 0.12, 0.23, 0.18, and 0.15, respectively.
a) Verify that this is a legitimate probability distribution.
b) Find the mean number of items selected.
c) Find the standard deviation of the number of items selected.

Answer 1

a) multiply each of the digits 1 through 5 by its respective probability, and then add up the products. If the sum = 1, then this is a valid probability distribution. Show all work, please.

Answer 2

1 x.32 = .32
2 x . 12 = .24
3 x .23 = .69
4 x . 18= .72
5 x .15 = .75
=2.72
@mathmale

Answer 3

is that right