A survey is taken to determine the number of cups of coffee a person likes to drink each day. The following probability distribution shows the proportion of people in each category.

Cups Per Day(x) P(x)

0 0.9

1 .10

2 .12

3 .40

4 .20

5 .09

a.) How can you tell that this actually is a probability distribution?

b.) Draw a graph of this probability distribution.

c.) Find the mean and standard deviation of this probability distribution.

d.) If a person is selected at random, what is the expected number of cups they like to drink?

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