The following contingency table shows the number of two-bedroom apartments
grouped by monthly rent and location.
The probability that a randomly selected apartment from this group has a monthly rental
from $800 to under $900 or is located in York is ________.
A) 0.536
B) 0.630
C) 0.729
D) 0.858
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. The critical value for this hypothesis test would be
________.
A) 1.96
B) 1.645
C) 2.33
D) 1.28
Nationwide Insurance would like to perform a chi-square test to investigate whether a
difference exists in the proportion of male and female teenagers who text while they
drive. A random sample of 80 male teenagers found that 50 indicated they texted while
driving. A random sample of 120 female teenagers found that 65 indicated they texted
while driving. The expected frequency of male teenagers who text is ________.
A) 30
B) 34
C) 46
D) 50
Use the following information to answer the question(s) below.
The National Basketball Association (NBA) would like to develop a multiple regression
model that would predict the number of wins for a team during the season. The
following independent variables were considered for the model: field goal percentage
(FG%), three-point percentage (3PT%), free throw percentage (FT%), turnovers per
game (TO), rebounds per game (REB), assists per game (ASSISTS), and steals per
game (STEALS). The following table shows the results of a general stepwise regression
procedure with “p-value to enter” and “p-value to remove” set to 0.05.
Predict the number of wins for a team with the following data:
Field goal percentage = 46.2%
Three-point percentage = 36.0%
Free throw percentage = 74.5%
Turnovers per game = 14.4
Rebounds per game = 43.7
Assists per game = 20.9
Steals per game = 7.0
A) 42.0
B) 49.7
C) 55.1
D) 58.3
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 the 95% prediction interval for the
number of passengers on a day when the ambient temperature is 23 degrees Celsius.
Use the information below to answer the following question(s).
Hats-R-Us would like to produce a new design of hats for the upcoming Major league
Baseball World Series. They need to decide to produce a large quantity or small
quantity of hats prior to the event starting. Eventual demand for this new design will be
strong or weak with a 50/50 chance of each level occurring. The following table shows
the payoff for each combination of production size and demand level, in thousands of
dollars.
Hats-R-Us also has the option of conducting a market survey at a cost of $10,000 to
acquire more accurate information about the likelihood of each demand level. If the
survey results are positive, there is an 83% probability that the eventual demand for the
new hat design will be strong. If the survey results are negative, there is a 23%
probability that the eventual demand for the new hat design will be strong.
Construct a decision tree to answer the following set of questions.
The expected monetary value, in thousands of dollars, for a small production quantity if
Hats-R-Us chooses not to conduct a market survey is _________.
A) $110.0
B) $137.5
C) $186.2
D) $211.0
The following data represent the end-of-month stock price of Facebook rounded to the
nearest dollar from June to December.
The predicted stock price for Facebook at the end of January using trend projection is
________.
A) $56.33
B) $60.29
C) $67.50
D) $69.35
All mathematical operations can be performed on ratio data.
The _________________ test is a nonparametric procedure that can be used to compare
two dependent samples.
A) Wilcoxon rank-sum
B) sign
C) Wilcoxon signed-rank
D) Kruskal-Wallis
Two real estate companies, Century 21 and RE/MAX, compete with one another in a
local market. The manager of the Century 21 office would like to advertise that homes
listed with RE/MAX average more than 10 days on the market when compared to
homes listed with his company. The following data shows the sample size and average
number of days on the market for the two companies along with the population standard
deviations.
If Population 1 is defined as RE/MAX and Population 2 is defined as Century 21, and
using α = 0.10, which one of the following statements is true? Because the p-value is
_________________
____________________________________________________________________.
A) greater than α, the manager at Century 21 can reject the null hypothesis and cannot
claim that homes listed with RE/MAX average more than 10 days on the market when
compared to homes listed with his company
B) greater than α, the manager at Century 21 can fail to reject the null hypothesis and
cannot claim that homes listed with RE/MAX average more than 10 days on the market
when compared to homes listed with his company
C) less than α, the manager at Century 21 can fail to reject the null hypothesis and can
claim that homes listed with RE/MAX average more than 10 days on the market when
compared to homes listed with his company
D) less than α, the manager at Century 21 can reject the null hypothesis and can claim
that homes listed with RE/MAX average more than 10 days on the market when
compared to homes listed with his company
Bananas are sold in bunches at a grocery store and typically consist of 4-8 bananas per
bunch. Suppose the weight of these bunches follows a normal distribution with a mean
of 3.54 pounds and a standard deviation of 0.63 pounds. What is the probability that a
randomly selected bunch of bananas will weigh less than 4.0 pounds?
A) 0.5080
B) 0.6808
C) 0.7673
D) 0.9821
The following data represents the number of home runs that Ryan Howard, a Major
League Baseball player for the Philadelphia Phillies, hit over a six-year period.
The median for this data set is ________.
A) 45
B) 46
C) 47
D) 48
AutoTrader.com would like to test if a difference exists in the age of three different
types of vehicles currently on the road–trucks, cars, and vans. The following data
represent the age of a random sample of trucks, cars, and vans.
The grand mean for these observations is ________.
A) 7.2
B) 8.0
C) 8.9
D) 9.3
When testing for the presence of positive autocorrelation and the Durbin-Watson
statistic is greater than the upper critical value, which one of the following statements is
true?
A) We fail to reject the null hypothesis and conclude that a positive autocorrelation is
present in the time series.
B) We fail to reject the null hypothesis and conclude that no positive autocorrelation is
present in the time series.
C) We reject the null hypothesis and conclude that a positive autocorrelation is present
in the time series.
D) The hypothesis test is inconclusive.
Costco sells paperback books in their retail stores and wanted to examine the
relationship between price and demand. The price of a particular novel was adjusted
each week and the weekly sales were recorded in the table below.
Management would like to use simple regression analysis to estimate weekly demand
for this novel using the price of the novel. The 95% prediction interval that estimates
the weekly sales for a price of $9 is ________.
A) (1.26, 13.86)
B) (3.39, 11.74)
C) (5.06, 10.06)
D) (6.36, 8.76)
The produce manager for a grocery store needs to decide how many heads of lettuce to
order each day. A head of lettuce sells for $1.20 and costs the grocery store $0.75. Any
unsold lettuce at the end of the day is donated to charity. If the manager purchases 100
heads of lettuce for tomorrow and demand for lettuce that day is 250 heads, the profit
will be ________.
A) “$68
B) $0
C) $45
D) $113
General Mills is considering offering a new type of yogurt. To gauge interest, they are
performing taste tests at different locations around the country. Based on the results of
these samples, they will decide whether or not to market the new yogurt. This is an
example of using
________________.
A) secondary data
B) qualitative data
C) descriptive statistics
D) inferential statistics
The following data represents the number of Sony TVs sold per day at a particular
Costco over a random sample of five business days.
The mode of this sample is ________.
A) 2
B) 4
C) 6
D) 7
Dempsey’s Garage repairs domestic and import cars. The following table shows the
number of cars that have been serviced by age and type during the last month.
The probability that a randomly selected car from this group was an import given that
the car was from 10 to under 15 years old is ________.
A) 0.373
B) 0.465
C) 0.625
D) 0.767
A golfer claims that his average golf score at the course he plays regularly is less than
90. A random sample of 35 rounds of golf was selected and the scores were recorded.
Assume that the standard deviation for the population of scores for this golfer is 3.4 and
the true population mean for scores for this golfer is 88.2. Using α = 0.05, beta equals
________.
A) 0.0694
B) 0.0944
C) 0.1292
D) 0.1895
The normal probability distribution can be used to approximate the ________
distribution when np ≥ 5 and nq ≥ 5.
A) exponential
B) Poisson
C) binomial
D) uniform
Sam’s Deli sells take-out baguette sandwiches for the lunchtime customers that sell for
$7.50 and cost Sam $4.75 to make. Any leftover sandwiches can be sold for $1.75 the
next day. Assume daily demand will be 50, 75, or 100 sandwiches with probabilities
0.20, 0.55, and 0.25 respectively. Sam needs to decide to make 50, 75, or 100
sandwiches each morning.
A) Determine the number of sandwiches that Sam should make each morning using
decision making under risk
B) Determine the expected value of perfect information.
State University offers several sections of a Business Statistics course in an in-class and
online format. Both formats are administered the same final exam each year. You have
been assigned to test the hypothesis that the average final exam score of in-class
students is different from the average final exam score of online students. The following
data summarizes the sample statistics for the final exam scores for students from each
format. Assume that the population variances are unequal.
If Population 1 is defined as in-class format and Population 2 is defined as online
format, the correct hypothesis statement for this hypothesis test would be
________________________.
A)
B)
C)
D)
Dempsey’s Garage repairs domestic and import cars. The following table shows the
number of cars that have been serviced by age and type during the last month.
The probability that a randomly selected car from this group was an import and from 5
to under 10 years old is ________.
A) 0.08
B) 0.15
C) 0.32
D) 0.50
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
weak is ________.
A) 0.584
B) 0.616
C) 0.696
D) 0.746
The class ________ represent the minimum and maximum values for each class of a
frequency distribution using grouped quantitative data.
A) boundaries
B) frequencies
C) widths
D) numbers
Medicare would like to test the hypothesis that the average monthly rate for
one-bedroom assisted-living facility is equal to $3,300. A random sample of 12
assisted-living facilities had an average rate of $3,690 per month. The standard
deviation for this sample was $530. Medicare would like to set α = 0.05. The test
statistic for this hypothesis test would be ________.
A) .
B) .
C) .
D) .
The National Association of Realtors reported that 26% of home buyers in the state of
Florida are foreigners. When testing the validity of this report, a Type I error would
occur if it was concluded that the proportion of foreign buyers was
______________________________.
A) more than 26% when, in reality, the proportion was 26% or less
B) not equal to 26% when, in reality, the proportion was equal to 26%
C) 26% or less when, in reality, the proportion was more than 26%
D) equal to 26% when, in reality, the proportion was not equal to 26%
A retail chain would like to test if a difference exists between the variability of
customer satisfaction scores from two locations. The following data represents
satisfaction scores from a random sample of customers from these locations on a scale
of 1-20.
The degrees of freedom for the critical value for Population 1 would be ________.
A) 4
B) 5
C) 6
D) 7
Jeff sells the New York Times Sunday newspaper at a city corner near several churches.
He sells each newspaper for $6.50 after purchasing them for $4.00. Any unsold
newspaper can be returned to the New York Times for a $0.75 credit. Jeff expects
demand on Sunday to be 75, 100, 125, or 150 newspapers and would like to order one
of these four quantities from the New York Times. If the Jeff uses the maximin
criterion, how many newspapers will he order?
A) 75
B) 100
C) 125
D) 150
The following distribution shows the frequency of daily revenue for an Italian
restaurant in Wilmington, Delaware.
What is the probability that a randomly selected day will generate more than $6,000 in
revenue?
A) 0.325
B) 0.650
C) 0.775
D) 0.900
In Delaware, cars are inspected each year using state-operated inspection centers. The
Wilmington center has three drive-through lanes where cars are inspected in a sequence
of steps. The following data show the number of minutes that a random sample of
drivers spent waiting and having their cars inspected in the three lanes each day of the
week.
The state of Delaware would like to perform a randomized block ANOVA to test for a
difference in the average times the drivers spend in the three lanes using the weekday as
a blocking factor with α = 0.05.. The conclusion for this hypothesis test would be that
because the blocking factor test statistic is
________________________________________________________________.
A) more than the blocking factor critical value, we can conclude that the blocking factor
was not effective
B) more than the blocking factor critical value, we can conclude that the blocking factor
was effective
C) less than the blocking factor critical value, we can conclude that the blocking factor
was not effective
D) less than the blocking factor critical value, we can conclude that the blocking factor
was effective
According to the Bureau of Labor Statistics, 7.1% of the labor force was recently
unemployed. A random sample of 100 employable adults was selected. Using the
normal approximation to the binomial distribution, what is the probability that fewer
than 11 people from this sample are unemployed?
A) 0.5574
B) 0.6539
C) 0.8217
D) 0.9066
A ________ component is defined as the unpredictable movements in a time series that
cannot be attributed to either trend, seasonal, or cyclical components.
A) business
B) dummy
C) random
D) forecasted
There are currently seven statistics classes being taught this semester at Wilmington
College. The following data represent the number of students in each class.
20 25 18 32 22 30 28
Determine the mode of this data set.
Note: The problems below are based on the following information:
The following data show the minutes that randomly selected flights were delayed from
their scheduled departure at three different airports throughout different time intervals
during the day.
If appropriate, perform a multiple comparison test to determine which pairs of airports
are different using .
The following table shows the number of points scored by the Green Bay Packers and
the Detroit Lions of the National Football League over 15 recent seasons.
Use four classes, each with a class width of 100. Start classes with 201-300, 301-400,
and so on, and construct a percentage polygon. What conclusions can you draw
comparing these two teams?
Use the following information to answer the question(s) below.
The following data provides the monthly Comcast cable bill for a random sample of 20
households along with the number of televisions in the household (TV), the number of
people living in the household (People), and the number of years that household has
been a Comcast customer (Years).
Show the calculations for the 95% confidence intervals to estimate the population
regression coefficients for the Comcast cable model and interpret their meaning.
The following data represents the satisfaction scores from customers at a hotel on a
1-100 scale.
Construct a stem and leaf display for this data, splitting the stems in half.
Use the information below to answer the following question(s).
The table below shows the number of interceptions thrown during the season by seven
randomly selected National Football League teams and the number of games those
teams won during the season.
Determine the correlation coefficient for this data and interpret its meaning.
Note: The problems below are based on the following information:
The following data show the minutes that randomly selected flights were delayed from
their scheduled departure at three different airports throughout different time intervals
during the day.
Perform a randomized block ANOVA using α = 0.05 to test if a difference exists in
average delay among these three airports.
A local Chamber of Commerce would like to test the hypothesis that the median
monthly rent for a one-bedroom apartment in York is different from the median rent of a
one-bedroom apartment in Lancaster. The following data summarizes the sample
statistics for one-bedroom apartment rents for both locations.
Perform this hypothesis test using α = 0.05.
Toll Brothers is a luxury home builder that would like to test the hypothesis that the
standard deviation for the size of new homes exceeds 500 square feet. The square
footage for a random sample of 25 new homes was recorded. The standard deviation for
this sample was found to be 610 square feet. Test this hypothesis using α = 0.10.