Question 1

The interquartile range contains the middle 50 percent of a data set.

Accepted Answer

A) True 
 B)False  True

Question 2

A professor wishes to develop a numerical method for giving grades.He intends to base the grade on homework,two midterms,a project,and a final examination.He wishes the final exam to have the largest influence on the grade.He wants the project to have 10%,each midterm to have 20%,and the homework to have 10% of the influence of the semester grade. Determine the weights the professor should use to produce a weighted average for grading purposes.

Accepted Answer

A)    
B)    
C)    
D)    
A)    
B)    
C)    
D)    A

Question 3

Which of the following statements is true?

Accepted Answer

A) The mean of a population will always be larger than the population standard deviation. 
B) The mean of the population will generally be larger than the mean of the sample selected from that population. 
C) The population mean and a sample mean for a sample selected from that population will usually be different values. 
D) The population mean and sample mean will always be identical. 
A) The mean of a population will always be larger than the population standard deviation. 
B) The mean of the population will generally be larger than the mean of the sample selected from that population. 
C) The population mean and a sample mean for a sample selected from that population will usually be different values. 
D) The population mean and sample mean will always be identical. C

Question 4

Which of the following measures is not affected by extreme values in the data?

Accepted Answer

A) The mean 
B) The median 
C) The range 
D) The standard deviation 
A) The mean 
B) The median 
C) The range 
D) The standard deviation

Question 5

If a set of data has 1,500 values,the 30th percentile value will correspond to the 450th value in the data when the data have been arranged in numerical order.

Accepted Answer

A) True 
 B)False

Question 6

Suppose a study of houses that have sold recently in your community showed the following frequency distribution for the number of bedrooms:
   Based on this information the mean number of bedrooms in houses that sold is approximately 3.26.

Accepted Answer

A) True 
 B)False

Question 7

You are given the following data:
   If these data were considered to be a population and you computed the mean,you would get the same answer as if these data were considered to be a sample from a larger population.

Accepted Answer

A) True 
 B)False

Question 8

At a sawmill in Oregon,a process improvement team measured the diameters for a sample of 1,500 logs.The following summary statistics were computed:   Given this information,which of the following statements is correct?

Accepted Answer

A) The distribution of log diameters is symmetric. 
B) A log that is over 20 inches in diameter can be considered an outlier. 
C) The distribution of log diameters is right-skewed. 
D) The distribution is left-skewed. 
A) The distribution of log diameters is symmetric. 
B) A log that is over 20 inches in diameter can be considered an outlier. 
C) The distribution of log diameters is right-skewed. 
D) The distribution is left-skewed.

Question 9

The range is an ideal measure of variation since it is not sensitive to extreme values in the data.

Accepted Answer

A) True 
 B)False

Question 10

The advantage of using the interquartile range versus the range as a measure of variation is:

Accepted Answer

A) it is easier to compute. 
B) it utilizes all the data in its computation. 
C) it gives a value that is closer to the true variation. 
D) it is less affected by extremes in the data. 
A) it is easier to compute. 
B) it utilizes all the data in its computation. 
C) it gives a value that is closer to the true variation. 
D) it is less affected by extremes in the data.

Question 11

Consumer products are required by law to contain at least as much as the amount printed on the package.For example a bag of potato chips that is labeled as 10 ounces should contain at least 10 ounces.Assume that the standard deviation of the packaging equipment yields a bag weight standard deviation of 0.2 ounces.Explain what average bag weight must be used to achieve at least 97.5 percent of the bags having 10 or more ounces in the bag.Assume the bag weight distribution is bell-shaped.

Accepted Answer

If the average bag weight were 10 ounces

Question 12

The second quartile for a set of data will have the same value as the 50th percentile only when the data are symmetric.

Accepted Answer

A) True 
 B)False

Question 13

When surveyed,a sample of 1,250 patients at a regional hospital provided interviewers with the following summary statistics pertaining to the hospital charges:
Minimum = $278.00 Q1 = $1,245 Q2 = $3,567 Q3= $4,702.
Based on these data,if you were to construct a box and whisker plot,the value $278 would be considered an outlier.

Accepted Answer

A) True 
 B)False

Question 14

A sample of people who have attended a college football game at your university has a mean = 3.2 members in their family.The mode number of family members is 2 and the median number is 2.0.Based on this information:

Accepted Answer

A) the population mean exceeds 3.2. 
B) the distribution is bell-shaped. 
C) the distribution is right-skewed. 
D) the distribution is left-skewed. 
A) the population mean exceeds 3.2. 
B) the distribution is bell-shaped. 
C) the distribution is right-skewed. 
D) the distribution is left-skewed.

Question 15

A large retail company gives an employment screening test to all prospective employees.If a prospective employee receives a report saying that she scored at the 40th percentile:

Accepted Answer

A) she scored above the median. 
B) she scored better than 40 percent of people who took the test. 
C) she scored in the top 40 percent of people who took the test. 
D) her z-score was a 40. 
A) she scored above the median. 
B) she scored better than 40 percent of people who took the test. 
C) she scored in the top 40 percent of people who took the test. 
D) her z-score was a 40.

Question 16

Based on the empirical rule we can assume that all bell-shaped distributions have approximately 95 percent of the values within ± 2 standard deviations of the mean.

Accepted Answer

A) True 
 B)False

Question 17

The Good-Guys Car Dealership has tracked the number of used cars sold at its downtown dealership.Consider the following data as representing the population of cars sold in each of the 8 weeks that the dealership has been open.
   The population variance is approximately 9.43.

Accepted Answer

A) True 
 B)False

Question 18

The following data reflect the number of customers who test drove new cars each day for a sample of 20 days at the Redfield Ford Dealership.   Given these data,what is the interquartile range?

Accepted Answer

A) 3 
B) 7 
C) 4 
D) 14 
A) 3 
B) 7 
C) 4 
D) 14

Question 19

Data was collected on the number of television sets in a household,and it was found that the mean was 3.5 and the standard deviation was 0.75. Based on these sample data,what is the standardized value corresponding to 5 televisions?

Accepted Answer

A) -2.00 
B) 1.5 
C) 2.00 
D) 1.125 
A) -2.00 
B) 1.5 
C) 2.00 
D) 1.125

Question 20

The Good-Guys Car Dealership has tracked the number of used cars sold at its downtown dealership.Consider the following data as representing the population of cars sold in each of the 8 weeks that the dealership has been open.
   The population range is 9.

Accepted Answer

A) True 
 B)False

The interquartile range contains the middle 50 percent of a data set.

Which of the following statements is true?

Which of the following measures is not affected by extreme values in the data?

If a set of data has 1,500 values,the 30^th percentile value will correspond to the 450^th value in the data when the data have been arranged in numerical order.

Suppose a study of houses that have sold recently in your community showed the following frequency distribution for the number of bedrooms: Based on this information the mean number of bedrooms in houses that sold is approximately 3.26.

You are given the following data: If these data were considered to be a population and you computed the mean,you would get the same answer as if these data were considered to be a sample from a larger population.

At a sawmill in Oregon,a process improvement team measured the diameters for a sample of 1,500 logs.The following summary statistics were computed: Given this information,which of the following statements is correct?

The range is an ideal measure of variation since it is not sensitive to extreme values in the data.

The advantage of using the interquartile range versus the range as a measure of variation is:

The second quartile for a set of data will have the same value as the 50^th percentile only when the data are symmetric.

A sample of people who have attended a college football game at your university has a mean = 3.2 members in their family.The mode number of family members is 2 and the median number is 2.0.Based on this information:

A large retail company gives an employment screening test to all prospective employees.If a prospective employee receives a report saying that she scored at the 40^th percentile:

Based on the empirical rule we can assume that all bell-shaped distributions have approximately 95 percent of the values within ± 2 standard deviations of the mean.

The Good-Guys Car Dealership has tracked the number of used cars sold at its downtown dealership.Consider the following data as representing the population of cars sold in each of the 8 weeks that the dealership has been open. The population variance is approximately 9.43.

The following data reflect the number of customers who test drove new cars each day for a sample of 20 days at the Redfield Ford Dealership. Given these data,what is the interquartile range?

Data was collected on the number of television sets in a household,and it was found that the mean was 3.5 and the standard deviation was 0.75. Based on these sample data,what is the standardized value corresponding to 5 televisions?

The Good-Guys Car Dealership has tracked the number of used cars sold at its downtown dealership.Consider the following data as representing the population of cars sold in each of the 8 weeks that the dealership has been open. The population range is 9.

The Where,Why,and How of Data Collection

Graphs,Charts and Tablesdescribing Your Data

Introduction to Probability

Discrete Probability Distributions

Introduction to Continuous Probability Distributions

Introduction to Sampling Distributions

Estimating Single Population Parameters

Introduction to Hypothesis Testing

Estimation and Hypothesis Testing for Two Population Parameters

Hypothesis Tests and Estimation for Population Variances

Analysis of Variance

Goodness-Of-Fit Tests and Contingency Analysis

Introduction to Linear Regression and Correlation Analysis

Multiple Regression Analysis and Model Building

Analyzing and Forecasting Time-Series Data

Introduction to Nonparametric Statistics

Introduction to Quality and Statistical Process Control

Filters

Exam 3: Describing Data Using Numerical Measures

The interquartile range contains the middle 50 percent of a data set.

Which of the following statements is true?

Which of the following measures is not affected by extreme values in the data?

If a set of data has 1,500 values,the 30th percentile value will correspond to the 450th value in the data when the data have been arranged in numerical order.

Suppose a study of houses that have sold recently in your community showed the following frequency distribution for the number of bedrooms: Based on this information the mean number of bedrooms in houses that sold is approximately 3.26.

You are given the following data: If these data were considered to be a population and you computed the mean,you would get the same answer as if these data were considered to be a sample from a larger population.

At a sawmill in Oregon,a process improvement team measured the diameters for a sample of 1,500 logs.The following summary statistics were computed: Given this information,which of the following statements is correct?

The range is an ideal measure of variation since it is not sensitive to extreme values in the data.

The advantage of using the interquartile range versus the range as a measure of variation is:

The second quartile for a set of data will have the same value as the 50th percentile only when the data are symmetric.

A sample of people who have attended a college football game at your university has a mean = 3.2 members in their family.The mode number of family members is 2 and the median number is 2.0.Based on this information:

A large retail company gives an employment screening test to all prospective employees.If a prospective employee receives a report saying that she scored at the 40th percentile:

Based on the empirical rule we can assume that all bell-shaped distributions have approximately 95 percent of the values within ± 2 standard deviations of the mean.

The Good-Guys Car Dealership has tracked the number of used cars sold at its downtown dealership.Consider the following data as representing the population of cars sold in each of the 8 weeks that the dealership has been open. The population variance is approximately 9.43.

The following data reflect the number of customers who test drove new cars each day for a sample of 20 days at the Redfield Ford Dealership. Given these data,what is the interquartile range?

Data was collected on the number of television sets in a household,and it was found that the mean was 3.5 and the standard deviation was 0.75. Based on these sample data,what is the standardized value corresponding to 5 televisions?

The Good-Guys Car Dealership has tracked the number of used cars sold at its downtown dealership.Consider the following data as representing the population of cars sold in each of the 8 weeks that the dealership has been open. The population range is 9.

The Where,Why,and How of Data Collection

Graphs,Charts and Tablesdescribing Your Data

Introduction to Probability

Discrete Probability Distributions

Introduction to Continuous Probability Distributions

Introduction to Sampling Distributions

Estimating Single Population Parameters

Introduction to Hypothesis Testing

Estimation and Hypothesis Testing for Two Population Parameters

Hypothesis Tests and Estimation for Population Variances

Analysis of Variance

Goodness-Of-Fit Tests and Contingency Analysis

Introduction to Linear Regression and Correlation Analysis

Multiple Regression Analysis and Model Building

Analyzing and Forecasting Time-Series Data

Introduction to Nonparametric Statistics

Introduction to Quality and Statistical Process Control

Filters

If a set of data has 1,500 values,the 30^th percentile value will correspond to the 450^th value in the data when the data have been arranged in numerical order.

The second quartile for a set of data will have the same value as the 50^th percentile only when the data are symmetric.

A large retail company gives an employment screening test to all prospective employees.If a prospective employee receives a report saying that she scored at the 40^th percentile: