Question

**Question 1**

The population of newborn babies (i.e., younger than 3 months old) produces an

average of μ = 12 dirty diapers with a standard deviation of σ = 4. If you randomly selected n = 36 newborn babies, how well on average will the sample represent the population (i.e., what is the expected difference between the sample and population mean by chance)?

Group of answer choices

a. 4 diaper difference

b. .667 diaper difference

c. .111 diaper difference

d. .894 diaper difference

e. .333 diaper difference

**Question 2**

A random sample of n = 36 scores is selected from a population. Which of the following distributions **definitely will be normal**?

Group of answer choices

a. Neither the sample, the population, nor the distribution of sample means will definitely be normal.

b. The sampling distribution will form a normal distribution.

c. The scores in the population will form a normal distribution.

d. The scores in the sample will form a normal distribution.

**Question 3**

Which of the following distributions **will definitely not be normal**?

Group of answer choices

a. The distribution of sample means with a sample size of n = 36 from a normally distributed population.

b. The distribution of sample means with a sample size of n = 36 from a population with a positive skew.

c. The distribution of sample means with a sample size of n = 16 from a normally distributed population.

d. The distribution of sample means with a sample size of n = 16 from a population with a positive skew.

**Question 4**

A population has μ = 80 with σ = 8. The **distribution of sample means **of size n = 4 selected from this population would have a value of ________ for the mean of sample means.

Group of answer choices

a. μm = 20

b. μm = 40

c. μm = 8

d. μm = 80

**Question 5**

A sample of n = 16 scores is obtained from a population with μ = 70 and σ = 20. What sample mean values are in the 20th percentile of the sampling distribution (i.e., the lowest 20% of all possible means of n = 16 from this population)?

Group of answer choices

a. sample means above 74.2

b. sample means at or below 74.2

c. sample means above 65.8

d. sample means at or below 65.8

e. sample means above 86.8

f. sample means at or below 86.8

g. sample means above 53.2

h. sample means at or below 53.2

**Question 6**

A sample is obtained from a population with μ = 50 and σ = 8. Which of the following samples is least likely (least probable)? Try using logic instead of calculations.

Group of answer choices

a. a sample of n = 4 scores with M = 52

b. a sample of n = 4 scores with M = 54

c. a sample of n = 16 scores with M = 52

d. a sample of n = 16 scores with M = 54

**Question 7**

A random sample of n = 4 scores is obtained from a normal population with μ = 20 and σ = 4. What is the probability of obtaining a mean greater than M = 24 for this sample?

Group of answer choices

a. p = .1587

b. p = .9772

c. p = .0228

d. p = .8413

e. p = .6915

f. p = .3085

**Question 8**

A random sample of n = 4 scores is obtained from a normal population with μ = 40 and σ = 6. What is the probability of obtaining a mean less than or equal to M = 43 for this sample?

Group of answer choices

a. p = .8413

b. p = .1587

c. p = .9772

d. p = .0228

e. p = .6915

f. p = .3085