# Question: A record store owner finds that 20 of customers entering

A record store owner finds that 20% of customers entering her store make a purchase. One morning 180 people, who can be regarded as a random sample of all customers, enter the store.

a. What is the mean of the distribution of the sample proportion of customers making a purchase?

b. What is the variance of the sample proportion?

c. What is the standard error of the sample proportion?

d. What is the probability that the sample proportion is less than 0.15?

a. What is the mean of the distribution of the sample proportion of customers making a purchase?

b. What is the variance of the sample proportion?

c. What is the standard error of the sample proportion?

d. What is the probability that the sample proportion is less than 0.15?

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