Psych. Stats Chap.7

A random sample of n = 16 scores is obtained from a population with σ = 12. If the sample mean is 6 points greater than the population mean, what is the z-score for the sample mean?

+2.00

A random sample of n = 16 scores is obtained from a normal population with μ = 40 and σ = 8. What is the probability that the sample mean will be within 2 points of the population mean?

0.68

A sample is selected from a population with μ = 50 and σ = 12. If the sample mean of M = 56 produces a z-score of z = +1.00, then how many scores are in the sample?

4

A sample of n = 4 scores has a standard error of 10 points. For the same population, what is the standard error for a sample of n = 16 scores?

5

A sample of n = 36 scores is selected from a population with σ = 12. If the sample mean of M = 56 produces a z-score of z = +3.00, then what is the population mean?

50

A sample of n = 4 scores is obtained from a population with μ = 70 and σ = 8. If the sample mean corresponds to a z-score of 2.00, what is the value of the sample mean?

78

A random sample of n = 16 scores is selected from a normal distribution with μ = 500 and σ = 200. For this sample, which of the following is true?

p(402<M<598)=0.95