Question 1

A random sample of size 30 is taken from a population with mean 50 and standard deviation 5.
-What is $\mu _ { \bar { x } }$ ?

Accepted Answer

The answer of A random sample of size 30 is...

Question 2

The sample variance s2 is an unbiased estimator of the population variance $\sigma ^ { 2 }$.

Accepted Answer

A) True 
 B)False

Question 3

If a sample size is at least _____,then for any sampled population,we can conclude that the sample means are approximately normal.

Accepted Answer

The answer of If a sample size is at least...

Question 4

Suppose you take a random sample from a normally distributed population with mean $\mu$= 175 and compute the sample mean $$\bar { x }$$ . If $$\sigma _ { \bar { x } } ^ { 2 }$$ = 9, find P( $$\bar { x }$$ > 172).

Accepted Answer

A) 0300 
B) 0100 
C) 1732 
D) 0577 
E) 8413 
A) 0300 
B) 0100 
C) 1732 
D) 0577 
E) 8413

Question 5

The internal auditing staff of a local manufacturing company performs a sample audit each quarter to estimate the proportion of accounts that are delinquent more than 90 days overdue. The historical records of the company show that over the past 8 years, 14 percent of the accounts are delinquent. For this quarter, the auditing staff randomly selected 250 customer accounts.
-What is the probability that at least 30 accounts will be classified as delinquent?

Accepted Answer

A) 0.3186 
B) 0.1814 
C) 0.8186 
D) 0.6372 
E) 0.7584 
A) 0.3186 
B) 0.1814 
C) 0.8186 
D) 0.6372 
E) 0.7584

Question 6

Whenever the sampled population has a normal distribution,the sampling distribution of $\bar { x }$Is normal:

Accepted Answer

A) for only large sample sizes. 
B) for only small sample sizes. 
C) for any sample size. 
D) for only samples of exactly 30. 
E) for only samples of sizes greater than 31. 
A) for only large sample sizes. 
B) for only small sample sizes. 
C) for any sample size. 
D) for only samples of exactly 30. 
E) for only samples of sizes greater than 31.

Question 7

It has been reported that the average time to download the home page from a government website was 0.9 seconds. Suppose that the download times were normally distributed with a standard deviation of 0.3 seconds. If random samples of 36 download times are selected:
-Describe the shape of the sampling distribution.How was this determined?

Accepted Answer

Normal because the o

Question 8

Find P ( $\bar { x }$ < 51.5).

Accepted Answer

The answer of Find P ( $\bar { x }$...

Question 9

What is $\sigma _ { \bar { x } }$ ?

Accepted Answer

The answer of What is \(\sigma _ { \bar {...

Question 10

A random sample of size 1,000 is taken from a population where, for some characteristic of the population, p = .20.
-Describe the shape of the sampling distribution of
$\hat { p }$.

Accepted Answer

@#IMG-DLM& 
.
Normal

Question 11

A manufacturing company measures the weight of boxes before shipping them to the customers. If the box weights have a population mean and standard deviation of 90 kg and 24 kg respectively, then based on a sample size of 36 boxes, the probability that the average weight of the boxes will:
-Be less than 84 kg is:

Accepted Answer

A) 0.1687 
B) 0.9332 
C) 0.4332 
D) 0.0668 
E) 0.8413 
A) 0.1687 
B) 0.9332 
C) 0.4332 
D) 0.0668 
E) 0.8413

Question 12

What is the probability that at least 70 patients will not be satisfied with the after-surgery care?

Accepted Answer

A) 0.8944 
B) 0.3944 
C) 0.1056 
D) 0.7888 
E) 0.8449 
A) 0.8944 
B) 0.3944 
C) 0.1056 
D) 0.7888 
E) 0.8449

Question 13

If we take a sample of any size from a population with mean $\mu$ 
and standard deviation $\sigma$ ,then the standard deviation of the sampling distribution of the sample mean $\bar { x }$ is $\sigma$ .

Accepted Answer

A) True 
 B)False

Question 14

A sample statistic is an unbiased point estimate of a population parameter if the mean of the populations of all possible values of the sample statistic equals the population parameter.

Accepted Answer

A) True 
 B)False

Question 15

Suppose you take a sample of size 4 from a population with a mean of 70 and a standard deviation of 10.Based on such a sample,what are the mean and standard deviation of the sampling distribution of $\bar { x }$
?

Accepted Answer

A)  $\mu _ { \bar { x } }$ = 70, $\sigma _ { \bar { x } }$ = 5 
B)  $\mu _ { \bar { x } }$ = 70, $\mu _ { \bar { x } }$ = 2.5 
C)  $\mu _ { \bar { x } }$ = 17.5, $\mu _ { \bar { x } }$ = 5 
D)  $\mu _ { \bar { x } }$ = 17.5, $\mu _ { \bar { x } }$ = 10 
E) Cannot be determined unless the sample size is at least 30. 
A)  $\mu _ { \bar { x } }$ = 70, $\sigma _ { \bar { x } }$ = 5 
B)  $\mu _ { \bar { x } }$ = 70, $\mu _ { \bar { x } }$ = 2.5 
C)  $\mu _ { \bar { x } }$ = 17.5, $\mu _ { \bar { x } }$ = 5 
D)  $\mu _ { \bar { x } }$ = 17.5, $\mu _ { \bar { x } }$ = 10 
E) Cannot be determined unless the sample size is at least 30.

Question 16

The _________ theorem allows us to approximate the sampling distribution of a sample mean with a normal probability distribution whenever the sample size is sufficiently large.

Accepted Answer

The answer of The _________ theorem allows us to approximate...

Question 17

A random sample of size 1,000 is taken from a population where, for some characteristic of the population, p = .20.
-Find P( $\hat { p }$ < .18).

Accepted Answer

The answer of A random sample of size 1,000 is...

Question 18

The standard deviation of all possible sample proportions increases as the sample size increases.

Accepted Answer

A) True 
 B)False

Question 19

If the sampled population has a normal distribution,then the sampling distribution of $\bar { x }$  is also normal regardless of the sample size.

Accepted Answer

A) True 
 B)False

Question 20

The population of all ___________ proportions is described by sampling distribution of $\hat { p }$.

Accepted Answer

The answer of The population of all ___________ proportions is...

A random sample of size 30 is taken from a population with mean 50 and standard deviation 5. -What is $\mu _ { \bar { x } }$ ?

The sample variance s² is an unbiased estimator of the population variance $\sigma ^ { 2 }$ .

If a sample size is at least _____,then for any sampled population,we can conclude that the sample means are approximately normal.

Suppose you take a random sample from a normally distributed population with mean $\mu$ = 175 and compute the sample mean $\bar { x }$ . If $\sigma _ { \bar { x } } ^ { 2 }$ = 9, find P( $\bar { x }$ > 172).

Whenever the sampled population has a normal distribution,the sampling distribution of $\bar { x }$ Is normal:

Find P ( $\bar { x }$ < 51.5).

What is $\sigma _ { \bar { x } }$ ?

A random sample of size 1,000 is taken from a population where, for some characteristic of the population, p = .20. -Describe the shape of the sampling distribution of $\hat { p }$ .

What is the probability that at least 70 patients will not be satisfied with the after-surgery care?

If we take a sample of any size from a population with mean $\mu$ and standard deviation $\sigma$ ,then the standard deviation of the sampling distribution of the sample mean $\bar { x }$ is $\sigma$ .

A sample statistic is an unbiased point estimate of a population parameter if the mean of the populations of all possible values of the sample statistic equals the population parameter.

Suppose you take a sample of size 4 from a population with a mean of 70 and a standard deviation of 10.Based on such a sample,what are the mean and standard deviation of the sampling distribution of $\bar { x }$ ?

The _________ theorem allows us to approximate the sampling distribution of a sample mean with a normal probability distribution whenever the sample size is sufficiently large.

A random sample of size 1,000 is taken from a population where, for some characteristic of the population, p = .20. -Find P( $\hat { p }$ < .18).

The standard deviation of all possible sample proportions increases as the sample size increases.

If the sampled population has a normal distribution,then the sampling distribution of $\bar { x }$ is also normal regardless of the sample size.

The population of all ___________ proportions is described by sampling distribution of $\hat { p }$ .

An Introduction to Business Statistics

Descriptive Statistics

Probability

Discrete Random Variables

Continuous Random Variables

Confidence Intervals

Hypothesis Testing

Statistical Inferences Based on Two Samples

Experimental Design and Analysis of Variance

Correlation Coefficient and Simple Linear Regression Analysis

Multiple Regression and Model Building

Nonparametric Methods

Chi-Square Tests

Decision Theory

Time Series Forecasting

Filters

Exam 6: Sampling Distributions

A random sample of size 30 is taken from a population with mean 50 and standard deviation 5. -What is μxˉ\mu _ { \bar { x } }μxˉ​ ?

The sample variance s2 is an unbiased estimator of the population variance σ2\sigma ^ { 2 }σ2 .

If a sample size is at least _____,then for any sampled population,we can conclude that the sample means are approximately normal.

Suppose you take a random sample from a normally distributed population with mean μ\muμ = 175 and compute the sample mean xˉ\bar { x }xˉ . If σxˉ2\sigma _ { \bar { x } } ^ { 2 }σxˉ2​ = 9, find P( xˉ\bar { x }xˉ > 172).

Whenever the sampled population has a normal distribution,the sampling distribution of xˉ\bar { x }xˉ Is normal:

Find P ( xˉ\bar { x }xˉ < 51.5).

What is σxˉ\sigma _ { \bar { x } }σxˉ​ ?

A random sample of size 1,000 is taken from a population where, for some characteristic of the population, p = .20. -Describe the shape of the sampling distribution of p^\hat { p }p^​ .

What is the probability that at least 70 patients will not be satisfied with the after-surgery care?

If we take a sample of any size from a population with mean μ\muμ and standard deviation σ\sigmaσ ,then the standard deviation of the sampling distribution of the sample mean xˉ\bar { x }xˉ is σ\sigmaσ .

A sample statistic is an unbiased point estimate of a population parameter if the mean of the populations of all possible values of the sample statistic equals the population parameter.

Suppose you take a sample of size 4 from a population with a mean of 70 and a standard deviation of 10.Based on such a sample,what are the mean and standard deviation of the sampling distribution of xˉ\bar { x }xˉ ?

The _________ theorem allows us to approximate the sampling distribution of a sample mean with a normal probability distribution whenever the sample size is sufficiently large.

A random sample of size 1,000 is taken from a population where, for some characteristic of the population, p = .20. -Find P( p^\hat { p }p^​ < .18).

The standard deviation of all possible sample proportions increases as the sample size increases.

If the sampled population has a normal distribution,then the sampling distribution of xˉ\bar { x }xˉ is also normal regardless of the sample size.

The population of all ___________ proportions is described by sampling distribution of p^\hat { p }p^​ .

An Introduction to Business Statistics

Descriptive Statistics

Probability

Discrete Random Variables

Continuous Random Variables

Confidence Intervals

Hypothesis Testing

Statistical Inferences Based on Two Samples

Experimental Design and Analysis of Variance

Correlation Coefficient and Simple Linear Regression Analysis

Multiple Regression and Model Building

Nonparametric Methods

Chi-Square Tests

Decision Theory

Time Series Forecasting

Filters

A random sample of size 30 is taken from a population with mean 50 and standard deviation 5. -What is $\mu _ { \bar { x } }$ ?

The sample variance s² is an unbiased estimator of the population variance $\sigma ^ { 2 }$ .

Suppose you take a random sample from a normally distributed population with mean $\mu$ = 175 and compute the sample mean $\bar { x }$ . If $\sigma _ { \bar { x } } ^ { 2 }$ = 9, find P( $\bar { x }$ > 172).

Whenever the sampled population has a normal distribution,the sampling distribution of $\bar { x }$ Is normal:

Find P ( $\bar { x }$ < 51.5).

What is $\sigma _ { \bar { x } }$ ?

A random sample of size 1,000 is taken from a population where, for some characteristic of the population, p = .20. -Describe the shape of the sampling distribution of $\hat { p }$ .

If we take a sample of any size from a population with mean $\mu$ and standard deviation $\sigma$ ,then the standard deviation of the sampling distribution of the sample mean $\bar { x }$ is $\sigma$ .

Suppose you take a sample of size 4 from a population with a mean of 70 and a standard deviation of 10.Based on such a sample,what are the mean and standard deviation of the sampling distribution of $\bar { x }$ ?

A random sample of size 1,000 is taken from a population where, for some characteristic of the population, p = .20. -Find P( $\hat { p }$ < .18).

If the sampled population has a normal distribution,then the sampling distribution of $\bar { x }$ is also normal regardless of the sample size.

The population of all ___________ proportions is described by sampling distribution of $\hat { p }$ .