Following are the heights in inches of 12 two-year-old apple trees. Assume that the popul: normally distributed. $\begin{array}{llllll} \hline 31.9 & 36.9 & 40.7 & 36.3 & 39.4 & 34.5 \\ \hline 36.9 & 37.2 & 40.3 & 42.0 & 41.0 & 39.3 \\ \hline \end{array}$ Construct a $99 \%$ confidence interval for the population standard deviation $\sigma$.

A) $1.85 < \sigma < 5.61$ B) $1.93 < \sigma < 5.86$ C) $1.98 < \sigma < 5.63$ D) $1.90 < \sigma < 6.09$ on is A) $1.85 < \sigma < 5.61$ B) $1.93 < \sigma < 5.86$ C) $1.98 < \sigma < 5.63$ D) $1.90 < \sigma < 6.09$ on is

The following MINITAB output presents a $95 \%$ confidence interval. $\begin{array}{ccccc} \hline{\text { The assumed sigma }=9.5959} \\ \text { Variable } & \mathrm{N} & \text { Mean } & \text { SE Mean } & 95 \% \mathrm{CI} \\ \mathrm{x} & 62 & 49.304 & 1.2187 & (46.915,51.693) \\ \hline \end{array}$ Fill in the blanks: We are_________ confident that the population mean is between________ _ and

A) 5%, 0, 49.304 B) 95%, 0, 49.304 C) 5%, 46.915, 51.693 D) 95%, 46.915, 51.693 A) 5%, 0, 49.304 B) 95%, 0, 49.304 C) 5%, 46.915, 51.693 D) 95%, 46.915, 51.693

Exam 7: Confidence Intervals and Sample Size

A previous analysis of paper boxes showed that the the standard deviation of their lengths is 13 millimeters. A packer wishes to find the 95% confidence interval for the Average length of a box. How many boxes does he need to measure to be accurate within 4 millimeters?

(Multiple Choice)

4.8/5

(36)

Question 21

$\text { Find the critical value } z _ { \alpha / 2 } \text { needed to construct a(n) } 79 \% \text { confidence interval. }$

(Multiple Choice)

4.9/5

(29)

Question 22

Find $\chi _ { \text {left } } ^ { 2 }$ and $\chi _ { \text {right } } ^ { 2 }$ for a $90 \%$ confidence interval using the chi-square distribution with 15 degrees of freedom.

(Multiple Choice)

4.8/5

(33)

Question 23

An economics professor randomly selected 100 millionaires in the United States. The average age of these millionaires was 54.8 years. If the standard deviation of the entire Population of millionaires is 7.9 years, find the 95% confidence interval for the mean age Of all United States millionaires.

(Multiple Choice)

4.9/5

(47)

Question 24

In a study of 100 new cars, 29 are white. Find $\hat { p }$ and $\hat { q }$ , where $\hat { p }$ is the proportion of new cars that are white.

(Multiple Choice)

4.9/5

(45)

Question 25

A random sample of magnesium concentrations (in parts per million, or ppm) in ground water from various locations follows. Estimate the mean concentration of magnesium in ppm with $90 \%$ confidence. Assume $\sigma = 20$ . 44 122 34 114 5 101 68 106 100 56 42 66 36 20 18 98 101 28 89 100 125 7 31 94 21 70 38 18 60 18 98 51 30 120 68

(Multiple Choice)

4.8/5

(42)

Question 26

A sample of 400 racing cars showed that 80 of them cost over $700,000. What is the 99% confidence interval for the true proportion of racing cars that cost over $700,000?

(Short Answer)

4.7/5

(33)

Question 27

In a survey of 246 registered voters, 132 of them wished to see Mayor Waffleskate lose her next election. Find a point estimate for the proportion of registered voters who wish To see Mayor Waffleskate defeated.

(Multiple Choice)

4.9/5

(44)

Question 28

One of the characteristics of the $t$ -distribution is that the curve never touches the __-axis.

(Short Answer)

4.8/5

(31)

Question 29

The are the number of values that are free to vary after a sample statistic has been computed.

(Short Answer)

4.8/5

(39)

Question 30

The formula for the confidence interval for a standard deviation is .

(Essay)

4.8/5

(35)

Question 31

The value of $\alpha / 2$ used in the figure below is $0.02$ . $The value of \alpha / 2 used in the figure below is 0.02 .$

(True/False)

4.8/5

(37)

Question 32

What is the value for 2 for a $98 \%$ confidence interval when $n = 12$ ?

(Multiple Choice)

4.9/5

(31)

Question 33

It was found that in a sample of 90 teenage boys, 70% of them have received speeding tickets. What is the 90% confidence interval of the true proportion of teenage boys who Have received speeding tickets?

(Multiple Choice)

4.9/5

(43)

Question 34

The winning team's score in 13 high school basketball games was recorded. If the sample mean is 54.3 points and the sample standard deviation is 13.0 points, find the 98% confidence interval of the true mean.

(Multiple Choice)

4.7/5

(36)

Question 35

Following are the heights in inches of 12 two-year-old apple trees. Assume that the popul: normally distributed. 31.9 36.9 40.7 36.3 39.4 34.5 36.9 37.2 40.3 42.0 41.0 39.3 Construct a $99 \%$ confidence interval for the population standard deviation $\sigma$ .

(Multiple Choice)

4.8/5

(35)

Question 36

A study of nickels showed that the the standard deviation of the weight of nickels is milligrams. A coin counter manufacturer wishes to find the 95% confidence interval for The average weight of a nickel. How many nickels does he need to weigh to obtain an Average accurate to within 20 milligrams?

(Multiple Choice)

4.9/5

(35)

Question 37

Use the given data to construct a confidence interval of the requested level. $x = 98 , n = 223$ , confidence level 99\%

(Multiple Choice)

4.7/5

(36)

Question 38

The following MINITAB output presents a $95 \%$ confidence interval. The assumed sigma =9.5959 Variable Mean SE Mean 95\% 62 49.304 1.2187 (46.915,51.693) Fill in the blanks: We are_ confident that the population mean is between _ and

(Multiple Choice)

5.0/5

(29)

Question 39

The value for $\chi ^ { 2 }$ for a $99 \%$ confidence interval when $n = 24$ is $9.262$ .

(True/False)

4.9/5

(32)

Question 40

A previous analysis of paper boxes showed that the the standard deviation of their lengths is 13 millimeters. A packer wishes to find the 95% confidence interval for the Average length of a box. How many boxes does he need to measure to be accurate within 4 millimeters?

$\text { Find the critical value } z _ { \alpha / 2 } \text { needed to construct a(n) } 79 \% \text { confidence interval. }$

Find $\chi _ { \text {left } } ^ { 2 }$ and $\chi _ { \text {right } } ^ { 2 }$ for a $90 \%$ confidence interval using the chi-square distribution with 15 degrees of freedom.

An economics professor randomly selected 100 millionaires in the United States. The average age of these millionaires was 54.8 years. If the standard deviation of the entire Population of millionaires is 7.9 years, find the 95% confidence interval for the mean age Of all United States millionaires.

In a study of 100 new cars, 29 are white. Find $\hat { p }$ and $\hat { q }$ , where $\hat { p }$ is the proportion of new cars that are white.

A sample of 400 racing cars showed that 80 of them cost over $700,000. What is the 99% confidence interval for the true proportion of racing cars that cost over $700,000?

In a survey of 246 registered voters, 132 of them wished to see Mayor Waffleskate lose her next election. Find a point estimate for the proportion of registered voters who wish To see Mayor Waffleskate defeated.

One of the characteristics of the $t$ -distribution is that the curve never touches the __-axis.

The are the number of values that are free to vary after a sample statistic has been computed.

The formula for the confidence interval for a standard deviation is .

The value of $\alpha / 2$ used in the figure below is $0.02$ . $The value of \alpha / 2 used in the figure below is 0.02 .$

What is the value for 2 for a $98 \%$ confidence interval when $n = 12$ ?

It was found that in a sample of 90 teenage boys, 70% of them have received speeding tickets. What is the 90% confidence interval of the true proportion of teenage boys who Have received speeding tickets?

The winning team's score in 13 high school basketball games was recorded. If the sample mean is 54.3 points and the sample standard deviation is 13.0 points, find the 98% confidence interval of the true mean.

Following are the heights in inches of 12 two-year-old apple trees. Assume that the popul: normally distributed. 31.9 36.9 40.7 36.3 39.4 34.5 36.9 37.2 40.3 42.0 41.0 39.3 Construct a $99 \%$ confidence interval for the population standard deviation $\sigma$ .

A study of nickels showed that the the standard deviation of the weight of nickels is milligrams. A coin counter manufacturer wishes to find the 95% confidence interval for The average weight of a nickel. How many nickels does he need to weigh to obtain an Average accurate to within 20 milligrams?

Use the given data to construct a confidence interval of the requested level. $x = 98 , n = 223$ , confidence level 99\%

The following MINITAB output presents a $95 \%$ confidence interval. The assumed sigma =9.5959 Variable Mean SE Mean 95\% 62 49.304 1.2187 (46.915,51.693) Fill in the blanks: We are_ confident that the population mean is between _ and

The value for $\chi ^ { 2 }$ for a $99 \%$ confidence interval when $n = 24$ is $9.262$ .

The Nature of Probability and Statistics

Frequency Distributions and Graphs

Data Description

Probability and Counting Rules

Discrete Probability Distributions

The Normal Distribution

Hypothesis Testing

Testing the Difference Between Two Means, Two Variances, and Two Proportions

Correlation and Regression

Other Chi-Square Tests

Analysis of Variance

Nonparametric Statistics

Sampling and Simulation

Filters

Exam 7: Confidence Intervals and Sample Size

A previous analysis of paper boxes showed that the the standard deviation of their lengths is 13 millimeters. A packer wishes to find the 95% confidence interval for the Average length of a box. How many boxes does he need to measure to be accurate within 4 millimeters?

Find the critical value zα/2 needed to construct a(n) 79% confidence interval. \text { Find the critical value } z _ { \alpha / 2 } \text { needed to construct a(n) } 79 \% \text { confidence interval. } Find the critical value zα/2​ needed to construct a(n) 79% confidence interval.

Find χleft 2\chi _ { \text {left } } ^ { 2 }χleft 2​ and χright 2\chi _ { \text {right } } ^ { 2 }χright 2​ for a 90%90 \%90% confidence interval using the chi-square distribution with 15 degrees of freedom.

An economics professor randomly selected 100 millionaires in the United States. The average age of these millionaires was 54.8 years. If the standard deviation of the entire Population of millionaires is 7.9 years, find the 95% confidence interval for the mean age Of all United States millionaires.

In a study of 100 new cars, 29 are white. Find p^\hat { p }p^​ and q^\hat { q }q^​ , where p^\hat { p }p^​ is the proportion of new cars that are white.

A sample of 400 racing cars showed that 80 of them cost over $700,000. What is the 99% confidence interval for the true proportion of racing cars that cost over $700,000?

In a survey of 246 registered voters, 132 of them wished to see Mayor Waffleskate lose her next election. Find a point estimate for the proportion of registered voters who wish To see Mayor Waffleskate defeated.

One of the characteristics of the ttt -distribution is that the curve never touches the __-axis.

The are the number of values that are free to vary after a sample statistic has been computed.

The formula for the confidence interval for a standard deviation is .

The value of α/2\alpha / 2α/2 used in the figure below is 0.020.020.02 .

What is the value for 2 for a 98%98 \%98% confidence interval when n=12n = 12n=12 ?

It was found that in a sample of 90 teenage boys, 70% of them have received speeding tickets. What is the 90% confidence interval of the true proportion of teenage boys who Have received speeding tickets?

The winning team's score in 13 high school basketball games was recorded. If the sample mean is 54.3 points and the sample standard deviation is 13.0 points, find the 98% confidence interval of the true mean.

Following are the heights in inches of 12 two-year-old apple trees. Assume that the popul: normally distributed. 31.9 36.9 40.7 36.3 39.4 34.5 36.9 37.2 40.3 42.0 41.0 39.3 Construct a 99%99 \%99% confidence interval for the population standard deviation σ\sigmaσ .

A study of nickels showed that the the standard deviation of the weight of nickels is milligrams. A coin counter manufacturer wishes to find the 95% confidence interval for The average weight of a nickel. How many nickels does he need to weigh to obtain an Average accurate to within 20 milligrams?

Use the given data to construct a confidence interval of the requested level. x=98,n=223x = 98 , n = 223x=98,n=223 , confidence level 99\%

The following MINITAB output presents a 95%95 \%95% confidence interval. The assumed sigma =9.5959 Variable Mean SE Mean 95\% 62 49.304 1.2187 (46.915,51.693) Fill in the blanks: We are_________ confident that the population mean is between________ _ and

The value for χ2\chi ^ { 2 }χ2 for a 99%99 \%99% confidence interval when n=24n = 24n=24 is 9.2629.2629.262 .

The Nature of Probability and Statistics

Frequency Distributions and Graphs

Data Description

Probability and Counting Rules

Discrete Probability Distributions

The Normal Distribution

Hypothesis Testing

Testing the Difference Between Two Means, Two Variances, and Two Proportions

Correlation and Regression

Other Chi-Square Tests

Analysis of Variance

Nonparametric Statistics

Sampling and Simulation

Filters

$\text { Find the critical value } z _ { \alpha / 2 } \text { needed to construct a(n) } 79 \% \text { confidence interval. }$

Find $\chi _ { \text {left } } ^ { 2 }$ and $\chi _ { \text {right } } ^ { 2 }$ for a $90 \%$ confidence interval using the chi-square distribution with 15 degrees of freedom.

In a study of 100 new cars, 29 are white. Find $\hat { p }$ and $\hat { q }$ , where $\hat { p }$ is the proportion of new cars that are white.

One of the characteristics of the $t$ -distribution is that the curve never touches the __-axis.

The value of $\alpha / 2$ used in the figure below is $0.02$ . $The value of \alpha / 2 used in the figure below is 0.02 .$

What is the value for 2 for a $98 \%$ confidence interval when $n = 12$ ?

Following are the heights in inches of 12 two-year-old apple trees. Assume that the popul: normally distributed. 31.9 36.9 40.7 36.3 39.4 34.5 36.9 37.2 40.3 42.0 41.0 39.3 Construct a $99 \%$ confidence interval for the population standard deviation $\sigma$ .

Use the given data to construct a confidence interval of the requested level. $x = 98 , n = 223$ , confidence level 99\%

The following MINITAB output presents a $95 \%$ confidence interval. The assumed sigma =9.5959 Variable Mean SE Mean 95\% 62 49.304 1.2187 (46.915,51.693) Fill in the blanks: We are_ confident that the population mean is between _ and

The value for $\chi ^ { 2 }$ for a $99 \%$ confidence interval when $n = 24$ is $9.262$ .