approximately normal.- Random samples are selected from a large right-skewed population, and the sample mean is
calculated. As the sample size increases, the sampling distribution of the sample mean
(A) remains skewed right with the same mean and the same standard deviation.
(B) remains skewed right with the same mean and a smaller standard deviation.
(C) becomes more symmetric with a smaller mean and a smaller standard deviation.
(D) becomes more symmetric with the same mean and a smaller standard deviation.
(E) becomes more symmetric with a smaller mean and the same standard deviation. - The following table shows a five-number summary of prices for residential properties in a small
city. If a random sample of 8 of these properties is selected, what is the approximate probability that
exactly 3 of them are priced below $60,000?
(A) 0.0037
(B) 0.2076
(C) 0.6785
(D) 0.7929
(E) 0.8862
When we use a normal model to approximate a binomial model, we get slightly different estimates.
Which of the following statements explains why?
(A) The binomial model is discrete, and the normal model is continuous.
(B) The binomial model is skewed, and the normal model is symmetric.
(C) The binomial model assumes sampling without replacement, and the normal model assumes
sampling with replacement.
(D) Both choices A and B are correct reasons for the different estimates.
(E) Both choices A and C are correct reasons for the different estimates.