# Question

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?

## Answer to relevant Questions

An administrator for a large group of hospitals believes that of all patients 30% will generate bills that become at least 2 months overdue. A random sample of 200 patients is taken. a. What is the standard error of the ...A random sample of 100 voters is taken to estimate the proportion of a state's electorate in favor of increasing the gasoline tax to provide additional revenue for highway repairs. What is the largest value that the standard ...Forty percent of students at small colleges have brought their own personal computers to campus. A random sample of 120 entering freshmen was taken. a. What is the standard error of the sample proportion bringing their own ...Monthly rates of return on the shares of a particular common stock are independent of one another and normally distributed with a standard deviation of 1.6. A sample of 12 months is taken. a. Find the probability that the ...Given a population with a mean of μ = 100 and a variance of σ2 = 900, the central limit theorem applies when the sample size is n ≥ 25. A random sample of size n = 30 is obtained. a. What are the mean and variance of the ...Post your question

0