A random sample of 150 mortgages in the state of Mississippi was randomly selected.
From this sample, 17 were found to be delinquent on their current payment. The
approximate standard error of the proportion for this sample is ________.
A) 0.0145
B) 0.0258
C) 0.0406
D) 0.0567
The Dean of the Business School at State University would like to test the hypothesis
that no difference exists between the average final exam grades for the Introduction to
Marketing course and the Introduction to Finance course. A random sample of eight
students who took both courses was selected and their final exam grades for each
course are shown below.
If Population 1 is defined as the Marketing exam scores and Population 2 is defined as
the Finance exam scores, the mean of the matched-pair differences is ________.
A) 14.8
B) 12.5
C) 8.3
D) 5.0
Costco installs automobile tires on a first-come first-serve basis. The total time a
customer needs to wait for the installation to be completed follows the normal
distribution with a mean time of 106.3 minutes and a standard deviation of 18.5
minutes. What is the probability that a randomly selected customer will wait more than
125 minutes for his or her tires to be installed?
A) 0.1562
B) 0.2090
C) 0.3409
D) 0.4920
Use the following information to answer the question(s) below.
Ford would like to develop a regression model that would predict the number of cars
sold per month by a dealership employee based on the employee’s number of years of
sales experience (Exp), the employee’s weekly base salary before commissions (Salary),
and the education level of the employee. There are three levels of education in the sales
forcehigh school degree, associate’s degree, and bachelor’s degree. The following
dummy variables have been defined.
The following Excel output shows the partially completed regression output from a
random sample of employees from the previous month.
An employee with a bachelor’s degree will average ________ more cars sales per
month than an employee with an associate’s degree.
A) 2.9845
B) 1.3553
C) 2.5638
D) 0.4207
A beach community on a barrier island has three real estate companies that list rental
properties by location which are classified as ocean-front, beach-block, or mid-island.
The following contingency table shows the number of properties listed by each
company along with their location.
The degrees of freedom for the critical value is ________.
A) 3
B) 4
C) 5
D) 6
The Department of Education would like to test the hypothesis that the average debt
load of graduating students with a Bachelor’s degree is equal to $17,000. A random
sample of 34 students had an average debt load of $18,200. It is believed that the
population standard deviation for student debt load is $4,200. The Department of
Education would like to set α = 0.05. Which one of the following statements is true?
A) Because the p-value is greater than α, we fail to reject the null hypothesis and cannot
conclude that the average debt load is not equal to $17,000.
B) Because the p-value is greater than α, we fail to reject the null hypothesis and
conclude that the average debt load is equal to $17,000.
C) Because the p-value is less than α, we fail to reject the null hypothesis and conclude
that the average debt load is not equal to $17,000.
D) Because the p-value is less than α, we reject the null hypothesis and conclude that
the average debt load is equal to $17,000.
The following data represent the number of sweatshirts sold for each of the past six
days for Hoys Department Store at the beach in Avalon, New Jersey.
Using a three-period simple moving average, the mean absolute deviation is ________.
A) 2.0
B) 3.6
C) 4.3
D) 9.7
According to a recent survey, 70% of 18- to 34-year-olds do not keep a budget. A
random sample of six 18- to 34-year-olds was selected. The probability that all six do
not keep a budget is ________.
A) 0.078
B) 0.118
C) 0.240
D) 0.333
Use the information below to answer the following question(s).
The Marseille Water Taxi ferries tourists from the harbor at Marseille, France, to the
Frioul Islands in the Mediterranean Sea. The table below shows the number of
passengers on the noontime ferry over seven randomly selected days along with the
current ambient temperature in degrees Celsius.
Use the Marseille Water Taxi data to calculate:
A) The standard error of the estimate.
B) The 95% confidence interval for the average number of passengers on a day when
the ambient temperature is 23 degrees Celsius.
The average math SAT score for incoming freshman at a particular college is 535 with a
standard deviation of 60. The coefficient of variation for SAT scores at this school is
______.
A) 11.2%
B) 13.9%
C) 15.6%
D) 18.0%
Randomized block ANOVA partitions the total sum of squares into the sum of squares
_________________________________.
A) between, within, and error
B) between, within, and block
C) between, block, and error
D) between and within
The power of the hypothesis test is the probability of __________________________.
A) correctly rejecting the null hypothesis
B) incorrectly rejecting the null hypothesis
C) correctly rejecting the alternative hypothesis
D) incorrectly rejecting the alternative hypothesis
According to Net Market Share, Microsoft’s Internet Explorer browser has 53.4% of the
global market. A random sample of 70 users was selected. What is the probability that
32 or more from this sample used Internet Explorer as their browser?
A) 0.7266
B) 0.8050
C) 0.9015
D) 0.9608
According to the Insurance Research Council, 14% of U.S. drivers are uninsured. A
random sample of seven drivers was selected. What is the probability that none of these
drivers are uninsured?
A) 0.1985
B) 0.2366
C) 0.2981
D) 0.3479
Use the information below to answer the following question(s).
A snack food producer is considering introducing a new product to the consumer
market. It can choose to build a new facility for production of the new product, use an
existing facility, or outsource the production to another company. The company
estimates that the probability of strong demand for this product to be 65% and the
probability of weak demand is estimated at 35%. The company also has the option to
hire a marketing research firm to conduct a study to provide additional information
about the demand that has the following track record:
•Historically, this research firm has predicted a strong demand when the eventual
demand was strong 80% of the time.
•Historically, this research firm has predicted a weak demand when the eventual
demand was weak 85% of the time.
Given that the survey predicts a weak demand, the probability that the eventual demand is
strong is ________.
A) 0.167
B) 0.226
C) 0.304
D) 0.355
Use the following information to answer the question(s) below.
A home appraisal company would like to develop a regression model that would predict
the selling price of a house based on the age of the house in years (Age), the living area
of the house in square feet (Living Area) and the number of bedrooms (Bedrooms). The
following Excel output shows the partially completed regression output from a random
sample of homes that have recently sold.
The predicted selling price for a home that is 12 years of age, has 2,500 square feet of
living area, and has four bedrooms is ________.
A) $395,240
B) $401,398
C) $410,366
D) $443,747
The following data represent the square footage of 10 three-bedroom condos for sale in
Hilton Head, South Carolina.
1,559 1,625 1,167 1,264 1,676
1,300 2,058 1,126 1,858 1,321
Determine the 80th percentile of this sample.
Use the following information to answer the question(s) below.
A home appraisal company would like to develop a regression model that would predict
the selling price of a house based on the age of the house in years (Age), the living area
of the house in square feet (Living Area) and the number of bedrooms (Bedrooms). The
following Excel output shows the partially completed regression output from a random
sample of homes that have recently sold.
The adjusted for this regression model is ________.
A) 0.5060
B) 0.5547
C) 0.6439
D) 0.7202
A histogram is the appropriate type of graph to display both quantitative and qualitative
data.
The following table shows a frequency distribution of the number of MacBook Air
laptops sold per day at a particular Best Buy.
What is the mean number of MacBook Air laptops sold per day?
A) 2.6
B) 3.0
C) 3.5
D) 3.9
Use the following information to answer the question(s) below.
Ford would like to develop a regression model that would predict the number of cars
sold per month by a dealership employee based on the employee’s number of years of
sales experience (Exp), the employee’s weekly base salary before commissions (Salary),
and the education level of the employee. There are three levels of education in the sales
forcehigh school degree, associate’s degree, and bachelor’s degree. The following
dummy variables have been defined.
The following Excel output shows the partially completed regression output from a
random sample of employees from the previous month.
When using best subsets regression with a model that has four independent variables, a
total of ________ different combinations of regression models will be considered.
A) 4
B) 12
C) 15
D) 18
Verizon Wireless would like to estimate the proportion of households that use cell
phones for their phone service without a land line. A random sample of 150 households
was selected and 48 relied strictly on cell phones for their service. Using this sample,
the point estimate for the proportion of households without land lines is ________.
A) 0.25
B) 0.32
C) 0.48
D) 0.53
Use the following information to answer the question(s) below.
Ford would like to develop a regression model that would predict the number of cars
sold per month by a dealership employee based on the employee’s number of years of
sales experience (Exp), the employee’s weekly base salary before commissions (Salary),
and the education level of the employee. There are three levels of education in the sales
forcehigh school degree, associate’s degree, and bachelor’s degree. The following
dummy variables have been defined.
The following Excel output shows the partially completed regression output from a
random sample of employees from the previous month.
The test statistic for testing the significance of the ED2 variable is ________.
A) 1.83
B) 2.26
C) 2.40
D) 2.69
A key metric in the cell phone industry is average revenue per user (ARPU) which
represents the average dollar amount that a customer spends per store visit. Recently,
AT&T reported their ARPU was $67.81. Suppose the standard deviation for this
population is $18.45. What is the probability that the ARPU will be between $62 and
$66 from a random sample of 35 customers?
A) 0.2496
B) 0.3553
C) 0.4470
D) 0.5619
_________________ statisticscan be used for data that is at the nominal or ordinal level
of measurement.
A) Nonparametric
B) Descriptive
C) Parametric
D) Quantitative
The Wall Street Journal reported that the average amount of time that a French person
spends eating lunch at a restaurant is 22 minutes. Perform a hypothesis test to determine
if a difference exists between the average time an American spends eating lunch when
compared to a person from France. The following data represents the time, in minutes,
that random French and American diners spent at lunch. Assume that the population
variances are equal.
If Population 1 is defined as French diners and Population 2 is defined as American
diners, which one of the following statements is true?
A) Because the 90% confidence interval does not include zero, we can conclude that the
average time an American spends at lunch is equal to the average time that French
diners spend at lunch.
B) Because the 90% confidence interval does not include zero, we can conclude that the
average time an American spends at lunch is different from the average time that French
diners spend at lunch.
C) Because the 90% confidence interval includes zero, we can conclude that the
average time an American spends at lunch is different from the average time that French
diners spend at lunch.
D) Because the 90% confidence interval includes zero, we cannot conclude that the
average time an American spends at lunch is different from the average time that French
diners spend at lunch.
Consider the following stem and leaf display.
Which of the following statements is correct?
A) There are a total of 10 data values in this data set.
B) The data value that occurs most often is 22.
C) This largest data value is 34.
D) The class 15-19 contains the most values.
The time that customers wait to be served at the delicatessen for a grocery store follows
the uniform distribution between 0 and 7 minutes. What is the probability that a
randomly selected customer will wait will be exactly 5 minutes at the deli?
A) 0.0
B) 0.2857
C) 0.4286
D) 0.7143
AT&T would like to test the hypothesis that the proportion of 18- to 34-year-old
Americans that own a cell phone is less than the proportion of 35- to 49-year-old
Americans. A random sample of 200 18- to 34-year-old Americans found that 126
owned a smartphone. A random sample of 175 35- to 49-year-old Americans found that
119 owned a smartphone. If Population 1 is defined as 18- to 34-year-old Americans
and Population 2 is defined as 35- to 49-year-old Americans, the test statistic for this
hypothesis test would be ________.
A)
B)
C)
D)
The Department of Transportation would like to investigate if a difference exists in the
proportion of flights that arrive on-time between Alaska Airlines, Delta Airlines,
Southwest Airlines, and United Airlines. The following data represent the number of
on-time flights from random samples taken from each airline.
The expected frequency of on-time flights from the United sample is ________.
A) 66
B) 82.5
C) 90
D) 99
A business school has 15 full-time faculty and seven of them have tenure. A random
sample of six faculty are randomly selected to form a committee. What is the standard
deviation of this distribution?
The following data represent the time between customer arrivals, in minutes, at a
drive-thru for a fast food restaurant.
2 4 1 0 6 4 1 2 5 3
Determine the mode of this data set.
Bank of New York would like to test the hypothesis that the average checking account
balance for younger customers (under 40 years old) is different from the average
checking account balance for older customers (40 or more years old). The following
data summarizes the sample statistics of the checking account balances for customers in
each age group. Assume that the population variances are unequal.
Define Population 1 as younger customers and Population 2 as older customers and use
the p-value approach to test this hypothesis with α = 0.05.
The average battery life of the iPhone is reported to be 6.0 hours by Apple. Assume that
the standard deviation for the battery life for this cell phone is 30 minutes. A random
sample of 50 iPhones had an average battery life of 5.7 hours. Use a 90% confidence
interval to test the validity of Apple’s claim.
Use the following information to answer the question(s) below.
Delmarva Power is a utility company that would like to predict the monthly heating bill
for a household in Kent County during the month of January. A random sample of 18
households in the county were selected and their January heating bill recorded. This
data is shown in the table below along with the square footage of the house (SF), the
age of the heating system in years (Age,) and the type of heating system (heat pump = 1
or natural gas = 0).
Show the calculations for the 95% confidence intervals to estimate the population
regression coefficients for the heating model and interpret their meaning.
Toll Brothers is a luxury home builder that would like to test the hypothesis that the
average size of new homes exceeds 2,400 square feet. A random sample of 36 newly
constructed homes had an average of 2,510 square feet. Assume that the standard
deviation of the size for all newly constructed homes is 480 square feet. Toll Brothers
would like to set α = 0.02. Use the p-value approach to test this hypothesis.
A local Chamber of Commerce would like to test the hypothesis that the average
monthly rent for a one-bedroom apartment in York is different from the average rent of
a one-bedroom apartment in Lancaster. The following data summarizes the sample
statistics for one-bedroom apartment rents for both locations. Assume that the
population variances are equal.
Define Population 1 as Lancaster apartments and Population 2 as York apartments and
use the critical value approach to test this hypothesis with α = 0.05.