Question 1

Heights of Men 
The heights of men in the USA are normally distributed with a mean of 68 inches and a standard deviation of 4 inches. ​ ​
-{Heights of Men Narrative} If the population of men's heights is not normally distributed,which,if any,of the previous questions can you answer?

Accepted Answer

The answer of  Heights of Men 
The heights of...

Question 2

Heights of Men 
The heights of men in the USA are normally distributed with a mean of 68 inches and a standard deviation of 4 inches. ​ ​
-{Heights of Men Narrative} What is the probability that a randomly selected man is taller than 70 inches?

Accepted Answer

The answer of  Heights of Men 
The heights of...

Question 3

Recall the rule of thumb used to indicate when the normal distribution is a good approximation of the sampling distribution for the sample proportion  .For the combination n = 50,p = 0.05,the rule is satisfied.

Accepted Answer

A) True 
 B)False

Question 4

For a sample size of 1,the sampling distribution of the mean is normally distributed:

Accepted Answer

A) regardless of the shape of the population. 
B) only if the population values are larger than 30. 
C) only if the population is normally distributed. 
D) None of these choices.

Question 5

A sample of size 25 is selected at random from a finite population.If the finite population correction factor is 0.63,then the population size is:

Accepted Answer

A) 25 
B) 66 
C) 41 
D) None of these choices.

Question 6

The standard deviation of  is also called the:

Accepted Answer

A) standard error of the difference between two sample means. 
B) standard deviation of the difference between the population means. 
C) normal approximation to the difference of two binomial random variables. 
D) None of these choices.

Question 7

Consider an infinite population with a mean of 100 and a standard deviation of 20.A random sample of size 64 is taken from this population.The standard deviation of the sample mean equals 2.50.

Accepted Answer

A) True 
 B)False

Question 8

Retirees
 A sample of 50 retirees is drawn at random from a normal population whose mean age and standard deviation are 75 and 6 years,respectively. ​ ​
-{Retirees Narrative} What is the probability that two randomly selected retirees are over 73 years of age?

Accepted Answer

The answer of Retirees
 A sample of 50 retirees is...

Question 9

The standard error of the mean:

Accepted Answer

A) is never larger than the standard deviation of the population. 
B) decreases as the sample size increases. 
C) measures the variability of the mean from sample to sample. 
D) All of these choices are true.

Question 10

The standard deviation of  is also called the:

Accepted Answer

A) standard error of the sample proportion. 
B) standard deviation of the population. 
C) standard deviation of the binomial. 
D) None of these choices.

Question 11

If two random samples of sizes 30 and 32 are selected independently from two populations with means 121 and 109,then the mean of the sampling distribution of the sample mean difference,  ,equals 12.

Accepted Answer

A) True 
 B)False

Question 12

If two random samples of sizes 30 and 36 are selected independently from two populations with means 78 and 85,and standard deviations 12 and 15,respectively,then the standard error of the difference  and  is equal to:

Accepted Answer

A) 0.904 
B) 3.324 
C) 3.391 
D) 0.833

Question 13

Heights of Fences 
Heights of fences are normally distributed with a mean of 52 inches and a standard deviation of 4 inches. ​ ​
-{Heights of Fences Narrative} Find the probability that one randomly selected fence is under 54 inches.

Accepted Answer

The answer of Heights of Fences 
Heights of fences are...

Question 14

In general,the binomial probability P(X ≥ x)is approximated by the area under the normal curve to the left of x − .5.

Accepted Answer

A) True 
 B)False

Question 15

The standard error of the sampling distribution of the sample proportion  ,when the sample size n = 100 and the population proportion p = 0.30,is 0.0021.

Accepted Answer

A) True 
 B)False

Question 16

Retirees
 A sample of 50 retirees is drawn at random from a normal population whose mean age and standard deviation are 75 and 6 years,respectively. ​ ​
-{Retirees Narrative} What is the probability that the mean age is at most 73 years?

Accepted Answer

The answer of Retirees
 A sample of 50 retirees is...

Question 17

Average Annual Revenue
 Suppose that the average annual revenue of a small business is $150,000 with a standard deviation of $40,000.Assume that the revenue distribution is normal. ​ ​
-{Average Annual Revenue Narrative} Could you have used a normal distribution to find an (approximate)probability for the average of 4 revenues if the population of revenues did not have a normal distribution?

Accepted Answer

The answer of  Average Annual Revenue
 Suppose that the...

Question 18

A sample of size 200 is taken at random from an infinite population.Given that the population proportion is 0.60,the probability that the sample proportion is between 0.58 and 0.62 is:

Accepted Answer

A) 0.4380 
B) 0.0320 
C) 0.0200 
D) None of these choices.

Question 19

A sampling distribution is defined as the probability distribution of means from all possible sample sizes that are taken from a given population.

Accepted Answer

A) True 
 B)False

Question 20

As the size of the sample is increased,the standard error of  decreases.

Accepted Answer

A) True 
 B)False

Exam 9: Sampling Distributions

Heights of Men The heights of men in the USA are normally distributed with a mean of 68 inches and a standard deviation of 4 inches. -{Heights of Men Narrative} If the population of men's heights is not normally distributed,which,if any,of the previous questions can you answer?

Heights of Men The heights of men in the USA are normally distributed with a mean of 68 inches and a standard deviation of 4 inches. -{Heights of Men Narrative} What is the probability that a randomly selected man is taller than 70 inches?

Recall the rule of thumb used to indicate when the normal distribution is a good approximation of the sampling distribution for the sample proportion .For the combination n = 50,p = 0.05,the rule is satisfied.

For a sample size of 1,the sampling distribution of the mean is normally distributed:

A sample of size 25 is selected at random from a finite population.If the finite population correction factor is 0.63,then the population size is:

The standard deviation of is also called the:

Consider an infinite population with a mean of 100 and a standard deviation of 20.A random sample of size 64 is taken from this population.The standard deviation of the sample mean equals 2.50.

Retirees A sample of 50 retirees is drawn at random from a normal population whose mean age and standard deviation are 75 and 6 years,respectively. -{Retirees Narrative} What is the probability that two randomly selected retirees are over 73 years of age?

The standard error of the mean:

The standard deviation of is also called the:

If two random samples of sizes 30 and 32 are selected independently from two populations with means 121 and 109,then the mean of the sampling distribution of the sample mean difference, ,equals 12.

If two random samples of sizes 30 and 36 are selected independently from two populations with means 78 and 85,and standard deviations 12 and 15,respectively,then the standard error of the difference and is equal to:

Heights of Fences Heights of fences are normally distributed with a mean of 52 inches and a standard deviation of 4 inches. -{Heights of Fences Narrative} Find the probability that one randomly selected fence is under 54 inches.

In general,the binomial probability P(X ≥ x)is approximated by the area under the normal curve to the left of x − .5.

The standard error of the sampling distribution of the sample proportion ,when the sample size n = 100 and the population proportion p = 0.30,is 0.0021.

Retirees A sample of 50 retirees is drawn at random from a normal population whose mean age and standard deviation are 75 and 6 years,respectively. -{Retirees Narrative} What is the probability that the mean age is at most 73 years?

A sample of size 200 is taken at random from an infinite population.Given that the population proportion is 0.60,the probability that the sample proportion is between 0.58 and 0.62 is:

A sampling distribution is defined as the probability distribution of means from all possible sample sizes that are taken from a given population.

As the size of the sample is increased,the standard error of decreases.

Exam 9: Sampling Distributions

Heights of Men The heights of men in the USA are normally distributed with a mean of 68 inches and a standard deviation of 4 inches. ​ ​ -{Heights of Men Narrative} If the population of men's heights is not normally distributed,which,if any,of the previous questions can you answer?

Heights of Men The heights of men in the USA are normally distributed with a mean of 68 inches and a standard deviation of 4 inches. ​ ​ -{Heights of Men Narrative} What is the probability that a randomly selected man is taller than 70 inches?

Recall the rule of thumb used to indicate when the normal distribution is a good approximation of the sampling distribution for the sample proportion .For the combination n = 50,p = 0.05,the rule is satisfied.

For a sample size of 1,the sampling distribution of the mean is normally distributed:

A sample of size 25 is selected at random from a finite population.If the finite population correction factor is 0.63,then the population size is:

The standard deviation of is also called the:

Consider an infinite population with a mean of 100 and a standard deviation of 20.A random sample of size 64 is taken from this population.The standard deviation of the sample mean equals 2.50.

Retirees A sample of 50 retirees is drawn at random from a normal population whose mean age and standard deviation are 75 and 6 years,respectively. ​ ​ -{Retirees Narrative} What is the probability that two randomly selected retirees are over 73 years of age?

The standard error of the mean:

The standard deviation of is also called the:

If two random samples of sizes 30 and 32 are selected independently from two populations with means 121 and 109,then the mean of the sampling distribution of the sample mean difference, ,equals 12.

If two random samples of sizes 30 and 36 are selected independently from two populations with means 78 and 85,and standard deviations 12 and 15,respectively,then the standard error of the difference and is equal to:

Heights of Fences Heights of fences are normally distributed with a mean of 52 inches and a standard deviation of 4 inches. ​ ​ -{Heights of Fences Narrative} Find the probability that one randomly selected fence is under 54 inches.

In general,the binomial probability P(X ≥ x)is approximated by the area under the normal curve to the left of x − .5.

The standard error of the sampling distribution of the sample proportion ,when the sample size n = 100 and the population proportion p = 0.30,is 0.0021.

Retirees A sample of 50 retirees is drawn at random from a normal population whose mean age and standard deviation are 75 and 6 years,respectively. ​ ​ -{Retirees Narrative} What is the probability that the mean age is at most 73 years?

A sample of size 200 is taken at random from an infinite population.Given that the population proportion is 0.60,the probability that the sample proportion is between 0.58 and 0.62 is:

A sampling distribution is defined as the probability distribution of means from all possible sample sizes that are taken from a given population.

As the size of the sample is increased,the standard error of decreases.

Heights of Men The heights of men in the USA are normally distributed with a mean of 68 inches and a standard deviation of 4 inches. -{Heights of Men Narrative} If the population of men's heights is not normally distributed,which,if any,of the previous questions can you answer?

Heights of Men The heights of men in the USA are normally distributed with a mean of 68 inches and a standard deviation of 4 inches. -{Heights of Men Narrative} What is the probability that a randomly selected man is taller than 70 inches?

Retirees A sample of 50 retirees is drawn at random from a normal population whose mean age and standard deviation are 75 and 6 years,respectively. -{Retirees Narrative} What is the probability that two randomly selected retirees are over 73 years of age?

Heights of Fences Heights of fences are normally distributed with a mean of 52 inches and a standard deviation of 4 inches. -{Heights of Fences Narrative} Find the probability that one randomly selected fence is under 54 inches.

Retirees A sample of 50 retirees is drawn at random from a normal population whose mean age and standard deviation are 75 and 6 years,respectively. -{Retirees Narrative} What is the probability that the mean age is at most 73 years?