Sampling Distributions - Means

2. It is the standard deviation symbol

• σ

• X

• N

• $\sqrt{a}$

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

• The Population
• The Sample
• The Sampling Distribution

Tags

CCSS.HSS.ID.A.4

CCSS.HSS.ID.A.2

CCSS.HSS.ID.A.3

The average speed of 1500 vehicles traveled on a stretch of highway that day is 67 miles per hour with a standard deviation of 3.5 miles per hour. If 100 vehicles are randomly selected as samples, what would be the mean of the resulting sampling distribution of sample means?

• 63.5

• 67

• 70.5

• 74

Tags

CCSS.HSS.IC.A.1

CCSS.HSS.IC.B.4

CCSS.HSS.MD.A.3

CCSS.HSS.MD.A.2

The standard deviation of a sampling distribution is the same as the standard deviation as the population.

• True

• False

Tags

CCSS.HSS.ID.A.4

If $\mu\ =\ 100$  and  $\sigma\ =\ 15$  and repeated samples of size 10 are taken, what are the mean and standard deviation of the sampling distribution?

•  $\mu_x=\ 100$  and  $\sigma_x\ =\ 15$  

•  $\mu_x=\ 100$  and  $\sigma_{\ x}\ =\ \frac{\sqrt{15}}{10}$  

•  $\mu_x=\ 100$  and  $\sigma_{x\ }=\frac{15}{\sqrt{10}}$  

•  $\mu_{x\ }=\ \frac{15}{\sqrt{10}}$  and  $\sigma_{x\ }=\ 100$  

Tags

CCSS.HSS.ID.A.4

What is the purpose of using a random method to get a sample?

• A.  Reduce bias.
• B.  Reduce variability.
• C.  Increase bias.
• D. Increase variability.

Tags

CCSS.HSS.IC.A.1

CCSS.HSS.IC.B.3

The mean weight of potato chip bags is 10.5 ounces with a standard deviation of 3 ounces. A random sample of 40 bags of potato chips is selected. What is the probability that the mean of the sample is less than 10 ounces?

• -1.05

• .146

• .020

• .853

Tags

CCSS.HSS.ID.A.4

CCSS.HSS.IC.A.1

CCSS.HSS.IC.B.4

CCSS.HSS.MD.A.3

The mean distance an OHS student travels to school is 5.6 miles with a standard deviation of 1.7 miles. Mrs. McLemore finds the mean of her 4th period class - a randomly selected sample of 39 students. What is the probability that the mean of her class is more than 6 miles?

• 0.002

• 0.070

• 0.898

• 1.27

Tags

CCSS.HSN.RN.A.2

The amount of fuel used by jumbo jets to take off is normally distributed with a mean of 4000 gallons and a standard deviation of 125 gallons.  What is the probability that the mean number of gallons of fuel needed to take off for a randomly selected sample of 40 jumbo jets will be less than 3950 gallons?

• .0057
• .025
• .345
• .781

Tags

CCSS.HSS.ID.A.4

CCSS.HSS.IC.A.1

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?

• .430
• .148
• .281
• .087

Tags

CCSS.HSS.ID.A.4

CCSS.HSS.IC.A.1

CCSS.HSS.IC.B.4

CCSS.HSS.MD.A.3