Question 1

The value for for a 99% confidence interval when is 9.262.

Accepted Answer

A) True 
 B)False

Question 2

John Davis, a manager of a supermarket, wants to estimate the proportion of customers that will be using discount coupons at his store.How large a sample is required to estimate the true proportion to within 3%
With 98% confidence?

Accepted Answer

A) 756 
B) 1,849 
C) 1,067 
D) 1,509 
A) 756 
B) 1,849 
C) 1,067 
D) 1,509

Question 3

Using Table G, find the values for   and   for   = 05 and n = 27.

Accepted Answer

A) 15.379 and 38.885 
B) 16.151 and 40.113 
C) 16.5395 and 40.725 
D) 16.928 and 41.337 
A) 15.379 and 38.885 
B) 16.151 and 40.113 
C) 16.5395 and 40.725 
D) 16.928 and 41.337

Question 4

Identify the confidence interval used in the figure below.

Accepted Answer

A) 90% 
B) 95% 
C) 98% 
D) 99% 
A) 90% 
B) 95% 
C) 98% 
D) 99%

Question 5

A confidence interval was constructed around a proportion.The interval was from 13.5% to 21.5%.The
proportion that was used to construct this interval was 17.5%.

Accepted Answer

A) True 
 B)False

Question 6

A sample of 1,108 was used to estimate a proportion with 98% confidence.If p = 0.5, what was the amount of error?

Accepted Answer

A) 0.040 
B) 0.025 
C) 0.035 
D) 0.028 
A) 0.040 
B) 0.025 
C) 0.035 
D) 0.028

Question 7

The t-distribution must be used when the sample size is greater than 30 and the variable is normally or
approximately normally distributed.

Accepted Answer

A) True 
 B)False

Question 8

The area under each chi-square distribution is equal to __________.
________________________________________

Accepted Answer

normally d

Question 9

In a study of 100 new cars, 29 of them were white.Find   and   where   is the proportion of new cars that is white.

Accepted Answer

A)    = 0.29,0.29   
B)    0.29,   = 0.71 
C)    = 0.71,0.29   
D)    0.71,   = 0.71 
A)    = 0.29,0.29   
B)    0.29,   = 0.71 
C)    = 0.71,0.29   
D)    0.71,   = 0.71

Question 10

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

Accepted Answer

maximum er

Question 11

A study of 100 apple trees showed that the average number of apples per tree was 2000.The standard deviation of the population is 150.Which of the following is the 95% confidence interval for the mean
Number of apples for all trees?

Accepted Answer

A) (1975.3, 2024.7) 
B) (1970.6, 2029.4) 
C) (1967.7, 2032.3) 
D) (1965.1, 2034.9) 
A) (1975.3, 2024.7) 
B) (1970.6, 2029.4) 
C) (1967.7, 2032.3) 
D) (1965.1, 2034.9)

Question 12

The value for for a 95% confidence interval when is 26.119.

Accepted Answer

A) True 
 B)False

Question 13

When computing a confidence interval for a population mean using raw data, round off to two more
decimal places than the number of decimal places in the original data.

Accepted Answer

A) True 
 B)False

Question 14

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

Accepted Answer

663 (661 u

Question 15

The width of a confidence interval for a population mean that is based on the t-distribution varies from
sample to sample even if the sample size and confidence level is kept fixed.

Accepted Answer

A) True 
 B)False

Question 16

A chi-square distribution is negatively skewed.

Accepted Answer

A) True 
 B)False

Question 17

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

Accepted Answer

A) 23.053 
B) 24.725 
C) 25.090 
D) 24.278 
A) 23.053 
B) 24.725 
C) 25.090 
D) 24.278

Question 18

A report states that 40% of home owners had a vegetable garden.How large a sample is needed to estimate the true proportion of home owners who have vegetable gardens to within 6% with 98%
Confidence?

Accepted Answer

A) 107 
B) 181 
C) 213 
D) 362 
A) 107 
B) 181 
C) 213 
D) 362

Question 19

The average number of mosquitos caught by 64 mosquito traps was 900 with a standard deviation of 100.
What is the 99% confidence interval for the true mean number of mosquitos caught by all mosquito traps?

Accepted Answer

The answer of The average number of mosquitos caught by...

Question 20

One of the characteristics of the t-distribution is that the curve never touches the __________.
________________________________________

Accepted Answer

The answer of One of the characteristics of the t-distribution...

The value for for a 99% confidence interval when is 9.262.

John Davis, a manager of a supermarket, wants to estimate the proportion of customers that will be using discount coupons at his store.How large a sample is required to estimate the true proportion to within 3% With 98% confidence?

Using Table G, find the values for and for = 05 and n = 27.

Identify the confidence interval used in the figure below.

A confidence interval was constructed around a proportion.The interval was from 13.5% to 21.5%.The proportion that was used to construct this interval was 17.5%.

A sample of 1,108 was used to estimate a proportion with 98% confidence.If p = 0.5, what was the amount of error?

The t-distribution must be used when the sample size is greater than 30 and the variable is normally or approximately normally distributed.

The area under each chi-square distribution is equal to . ______________________________

In a study of 100 new cars, 29 of them were white.Find and where is the proportion of new cars that is white.

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

A study of 100 apple trees showed that the average number of apples per tree was 2000.The standard deviation of the population is 150.Which of the following is the 95% confidence interval for the mean Number of apples for all trees?

The value for for a 95% confidence interval when is 26.119.

When computing a confidence interval for a population mean using raw data, round off to two more decimal places than the number of decimal places in the original data.

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

The width of a confidence interval for a population mean that is based on the t-distribution varies from sample to sample even if the sample size and confidence level is kept fixed.

A chi-square distribution is negatively skewed.

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

A report states that 40% of home owners had a vegetable garden.How large a sample is needed to estimate the true proportion of home owners who have vegetable gardens to within 6% with 98% Confidence?

The average number of mosquitos caught by 64 mosquito traps was 900 with a standard deviation of 100. What is the 99% confidence interval for the true mean number of mosquitos caught by all mosquito traps?

One of the characteristics of the t-distribution is that the curve never touches the . ______________________________

The Nature of Probability and Statistics

Frequency Distributions and Graphs

Data Description

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

The value for for a 99% confidence interval when is 9.262.

John Davis, a manager of a supermarket, wants to estimate the proportion of customers that will be using discount coupons at his store.How large a sample is required to estimate the true proportion to within 3% With 98% confidence?

Using Table G, find the values for and for = 05 and n = 27.

Identify the confidence interval used in the figure below.

A confidence interval was constructed around a proportion.The interval was from 13.5% to 21.5%.The proportion that was used to construct this interval was 17.5%.

A sample of 1,108 was used to estimate a proportion with 98% confidence.If p = 0.5, what was the amount of error?

The t-distribution must be used when the sample size is greater than 30 and the variable is normally or approximately normally distributed.

The area under each chi-square distribution is equal to __________. ________________________________________

In a study of 100 new cars, 29 of them were white.Find and where is the proportion of new cars that is white.

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

A study of 100 apple trees showed that the average number of apples per tree was 2000.The standard deviation of the population is 150.Which of the following is the 95% confidence interval for the mean Number of apples for all trees?

The value for for a 95% confidence interval when is 26.119.

When computing a confidence interval for a population mean using raw data, round off to two more decimal places than the number of decimal places in the original data.

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

The width of a confidence interval for a population mean that is based on the t-distribution varies from sample to sample even if the sample size and confidence level is kept fixed.

A chi-square distribution is negatively skewed.

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

A report states that 40% of home owners had a vegetable garden.How large a sample is needed to estimate the true proportion of home owners who have vegetable gardens to within 6% with 98% Confidence?

The average number of mosquitos caught by 64 mosquito traps was 900 with a standard deviation of 100. What is the 99% confidence interval for the true mean number of mosquitos caught by all mosquito traps?

One of the characteristics of the t-distribution is that the curve never touches the __________. ________________________________________

The Nature of Probability and Statistics

Frequency Distributions and Graphs

Data Description

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

The area under each chi-square distribution is equal to . ______________________________

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

One of the characteristics of the t-distribution is that the curve never touches the . ______________________________