10.23 Central Limit Theorem

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

The mean and standard deviation of a population are 400 and 40, respectively. Sample size is 25. 
What is the standard error of the sampling distribution?

• 400
• 40
• 25
• 8

Tags

CCSS.HSS.ID.A.4

 A group of 625 students has a mean age of 15.8 years with a standard deviation of 0.6 years.  The ages are normally distributed. What is the probability that a randomly selected student is older than 16.5 years old?

• 0.864
• 0.879
• 0.121
• None of these

Tags

CCSS.HSS.ID.A.4

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

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?

• .236
• .429
• .571
• .614

Tags

CCSS.HSS.ID.A.4

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

REVIEW!

Find the area of the shaded region if the z-score is -0.3

• 0.6179

• 0.488

• 0.3783

• 0.3821

Tags

CCSS.HSS.ID.A.4

If the population mean is 100 and the standard deviation is 20, what is the probability that the sample mean of 25 samples is less than 95?

• 0.1587

• 0.8413

• 0.0228

• 0.5000

Tags

CCSS.HSS.ID.A.4

If a population has a mean of 50 and a standard deviation of 10, what is the mean of the sampling distribution for a sample size of 36?

• 45

• 48

• 50

• 52

What is the formula for calculating the standard error of the mean?

• Standard Error (SE) = σ / √n

• Standard Error (SE) = n / σ

• Standard Error (SE) = σ * √n

• Standard Error (SE) = σ + n