Number of Fish Tanks The following data give the number of fish tanks owned for a population of 4 families. \[\begin{array} { | l | c c c c | } \hline \text { Family } & \text { A } & \text { B } & \text { C } & \text { D } \\ \hline \text { Number af Fish Tanks Owned } & 2 & 1 & 4 & 3 \\ \hline \end{array}\] -{Number of Fish Tanks Narrative} A sample of size 2 is drawn at random from the population.Use the formulas $\mu _ { \bar { x } } = \mu$ and $\sigma _ { \bar { x } } = \frac { \sigma } { \sqrt { n } } \sqrt { \frac { N - n } { N - 1 } }$ to calculate the mean and the standard deviation of the sampling distribution of the sample means.

The answer of Number of Fish Tanks The following data give...

Exam 9: Sampling Distributions

DVD Rental Store A DVD rental store wants to know what proportion of its customers are under age 21.A simple random sample of 500 customers was taken,and 375 of them were under age 21.Presume that the true population proportion of customers under age 21 is 0.68. -{DVD Rental Store Narrative} What is the probability that the sample proportion $\hat { p }$ is within 0.03 of the true proportion of customers who are under age 21?

(Essay)

4.9/5

(46)

Question 21

If all possible samples of size n are drawn from an infinite population with a mean of 15 and a standard deviation of 5,then the standard error of the sample mean equals 1.0 for samples of size:

(Multiple Choice)

4.9/5

(40)

Question 22

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 less than 0.58 is

(Multiple Choice)

4.8/5

(30)

Question 23

If the population is normal,then $\bar { X }$ is normally distributed for __________________ values of n.

(Essay)

4.8/5

(35)

Question 24

Suppose X has a distribution that is not normal.The Central Limit Theorem is important in this case because:

(Multiple Choice)

4.9/5

(34)

Question 25

Suppose it is known that 60% of radio listeners at a particular college are smokers.A sample of 500 students from the college is selected at random.Approximate the probability that at least 280 of these students are radio listeners.

(Essay)

4.9/5

(44)

Question 26

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 the mean height of a random sample of 36 men is greater than 70 inches?

(Essay)

4.9/5

(42)

Question 27

If the population distribution is skewed,in most cases the sampling distribution of the sample mean can be approximated by the normal distribution if the samples contain at least 30 observations.

(True/False)

4.9/5

(35)

Question 28

The finite population correction factor should be used:

(Multiple Choice)

4.8/5

(37)

Question 29

College Dean A college dean would like to estimate a population mean to within 40 units with 99% confidence given that the population standard deviation is 200. -When a great many simple random samples of size n are drawn from a population that is normally distributed,the sampling distribution of the sample mean is normal regardless of the sample size n.

(True/False)

4.7/5

(28)

Question 30

If two random samples of size 36 each are selected independently from two populations with variances 25 and 16,then the standard error of the sampling distribution of the sample mean difference, $\bar { X } _ { 1 } - \bar { X } _ { 2 }$ ,is 5- 4 = 1.

(True/False)

4.8/5

(40)

Question 31

Suppose that 100 items are drawn from a population of manufactured products and the weight,X,of each item is recorded.Prior experience has shown that the weight has a non-normal probability distribution with $\mu$ = 8 ounces and $\sigma$ = 3 ounces.Which of the following is true about the sampling of $\bar { X }$ ?

(Multiple Choice)

4.9/5

(42)

Question 32

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:

(Multiple Choice)

4.9/5

(40)

Question 33

Two samples are selected independently from two normal populations and the mean and standard error of the sampling distribution of $\bar { X } _ { 1 } - \bar { X } _ { 2 }$ are 32 and 38.72,respectively.Calculate P( $\bar { X } _ { 1 } - \bar { X } _ { 2 }$ > 0).

(Essay)

4.8/5

(44)

Question 34

Number of Fish Tanks The following data give the number of fish tanks owned for a population of 4 families. Family A B C D Number af Fish Tanks Owned 2 1 4 3 -{Number of Fish Tanks Narrative} A sample of size 2 is drawn at random from the population.Use the formulas $\mu _ { \bar { x } } = \mu$ and $\sigma _ { \bar { x } } = \frac { \sigma } { \sqrt { n } } \sqrt { \frac { N - n } { N - 1 } }$ to calculate the mean and the standard deviation of the sampling distribution of the sample means.

(Essay)

4.7/5

(42)

Question 35

Graduate Internships The chairman of the Biology department in a certain college believes that 70% of the department's graduate internships are given to international students.A random sample of 50 graduate interns is taken. -{Graduate Internships Narrative} What is the probability that the sample proportion $\hat { p }$ is between 0.65 and 0.73?

(Essay)

4.8/5

(37)

Question 36

{Heights of Fence Narrative} Find the probability that two randomly selected fences are both under 54 inches.

(Essay)

4.8/5

(40)

Question 37

The standard error of the difference between sample means, $\bar { X } _ { 1 } - \bar { X } _ { 2 }$ ,is calculated by the formula $\sigma _ { \bar { x } _ { 1 } - \bar { x } _ { 2 } } = \sqrt { \sigma _ { 1 } ^ { 2 } / n _ { 1 } - \sigma _ { 2 } ^ { 2 } / n _ { 2 } }$ where $\sigma _ { i } ^ { 2 }$ is the variance of population i (i = 1,2).

(True/False)

4.9/5

(38)

Question 38

What is the probability that you get more than 200 heads if you flip a coin 400 times?

(Essay)

4.8/5

(49)

Question 39

Given an infinite population with a mean of 75 and a standard deviation of 12,the probability that the mean of a sample of 36 observations,taken at random from this population,is less than 78 is:

(Multiple Choice)

4.8/5

(39)

Question 40

Showing 21 - 40 of 150

Exam 9: Sampling Distributions

If all possible samples of size n are drawn from an infinite population with a mean of 15 and a standard deviation of 5,then the standard error of the sample mean equals 1.0 for samples of size:

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 less than 0.58 is

If the population is normal,then Xˉ\bar { X }Xˉ is normally distributed for __________________ values of n.

Suppose X has a distribution that is not normal.The Central Limit Theorem is important in this case because:

Suppose it is known that 60% of radio listeners at a particular college are smokers.A sample of 500 students from the college is selected at random.Approximate the probability that at least 280 of these students are radio listeners.

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 the mean height of a random sample of 36 men is greater than 70 inches?

If the population distribution is skewed,in most cases the sampling distribution of the sample mean can be approximated by the normal distribution if the samples contain at least 30 observations.

The finite population correction factor should be used:

If two random samples of size 36 each are selected independently from two populations with variances 25 and 16,then the standard error of the sampling distribution of the sample mean difference, Xˉ1−Xˉ2\bar { X } _ { 1 } - \bar { X } _ { 2 }Xˉ1​−Xˉ2​ ,is 5- 4 = 1.

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:

{Heights of Fence Narrative} Find the probability that two randomly selected fences are both under 54 inches.

What is the probability that you get more than 200 heads if you flip a coin 400 times?

Given an infinite population with a mean of 75 and a standard deviation of 12,the probability that the mean of a sample of 36 observations,taken at random from this population,is less than 78 is:

What Is Statistics

Graphical Descriptive Techniques I

Graphical Descriptive Techniques II

A: Numerical Descriptive Techniques

B: Numerical Descriptive Techniques

C: Numerical Descriptive Techniques

Data Collection and Sampling

Probability

A: Random Variables and Discrete Probability Distributions

B: Random Variables and Discrete Probability Distributions

Continuous Probability Distributions

Introduction to Estimation

Introduction to Hypothesis Testing

Inference About a Population

Inference About Comparing Two Populations

Analysis of Variance

Chi-Squared Tests

A: Simple Linear Regression and Correlation

B: Simple Linear Regression and Correlation

Multiple Regression

Model Building

Nonparametric Statistics

Time-Series Analysis and Forecasting

Statistical Process Control

Decision Analysis

Conclusion

Filters

If the population is normal,then $\bar { X }$ is normally distributed for __________________ values of n.

If two random samples of size 36 each are selected independently from two populations with variances 25 and 16,then the standard error of the sampling distribution of the sample mean difference, $\bar { X } _ { 1 } - \bar { X } _ { 2 }$ ,is 5- 4 = 1.