AP Stats Ch9 review quiz

What happens to the shape of a sampling distribution of sample means as n increases?

• The skew gets bigger

• The skew is reversed

• It becomes narrower and more normal.

• The shape is the same, but wider

The mean and standard deviation of a population are 400 and 40, respectively. Sample size is 25.

What is the mean of the sampling distribution?

• 400

• 40

• 25

• 8

Tags

CCSS.HSS.MD.A.2

CCSS.HSS.MD.A.3

These symbols represent the mean and standard deviation for which of the following distributions?

• The Population

• The sample

• The sampling distribution (mean)

• The sampling distribution (proportion)

Tags

CCSS.HSS.ID.A.2

CCSS.HSS.ID.A.3

CCSS.HSS.ID.A.4

Researches found that boys playing high school football absorb an average of 355 hits to the head with a standard deviation of 80 hits during a season. What is the probability on a randomly selected team of 48 players that the average number of head hits per player is between 340 and 360?

• Approximately 0.0418

• Approximately 0.09

• Approximately 0.57

• Approximately 0.67

• Approximately 0.9582

Tags

CCSS.HSS.IC.A.1

CCSS.HSS.ID.A.4

CCSS.HSS.MD.A.3

Suppose the teenagers that attend public high schools get an average of 5.7 hours of sleep each night with a standard deviation of 1.7 hours. What is the probability that a randomly selected group of 35 high school students get more than 6 hours of sleep each night?

• Approximately 0.15

• Approximately 0.43

• Approximately 0.57

• Approximately 0.85

Tags

CCSS.HSS.IC.A.1

CCSS.HSS.IC.B.4

CCSS.HSS.ID.A.4

CCSS.HSS.MD.A.3

A group of 625 students has a mean age of 15.8 years with a standard deviation of 6 years. The ages are normally distributed. What is the probability that a randomly selected student is older than 16.5 years old?

• 0.0018

• 0.9982

• 2.92

• None of these

Tags

CCSS.HSS.ID.A.4

True or False:

The mean of the sample means is equal to the mean of the population.

• True

• False

Tags

CCSS.HSS.IC.A.1

CCSS.HSS.IC.B.4