QBA FINAL EXAM UPDATED
QUESTIONS AND CORRECT ANSWERS.
Businesses in a country are listed by size: small, medium, and large. Explain why business size is
an example of an ordinal-scaled variable. - ANS The size of a business is ordinal-scaled
because it has values that can be used as an order or rank of a categorical variable.
Suppose that you measure the time it takes to download a video from the internet.
a. Explain why the download time is a continuous numerical variable.
b. Explain why the download time is a ratio scaled variable. - ANS a) Download time is a
continuous numerical variable because it has numerical values that arise from a measuring
process.
b) Download times are numerical values that imply order and also have a true zero point.
You want to select a random sample of
n=1 from a population of three items (which are called A, B, and C). The rule for selecting the
sample is as follows: Flip a coin; if it is heads, pick item A; if it is tails, flip the coin again; this
time, if it is heads, choose B; if it is tails, choose C. Explain why this is a probability sample but
not a simple random sample. - ANS This is a probability sample because the probability of
each outcome is known, but it is not a simple random sample because there is a higher
probability of picking item A than there is of picking item B or of picking item C.
A hotel management company runs 10 hotels in a resort area. The hotels have a mix of
pricing—some hotels have budget-priced rooms, some have moderate-priced rooms, and some
have deluxe-priced rooms. Data are collected that indicate the number of rooms that are
occupied at each hotel on each day of a month. Explain how the 10 hotels can be recoded into
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, these three price categories. - ANS Create three new categorical variables, one for each type
of priced room. Determine which hotels include budget-priced rooms and reassign all data for
those hotels to a new categorical variable, budget-priced hotels. Determine which hotels
include moderate-priced rooms and reassign all data for those hotels to a new categorical
variable, moderate-priced hotels. Determine which hotels include deluxe-priced rooms and
reassign all data for those hotels to a new categorical variable, deluxe-priced hotels.
A recent corporate survey indicated that companies that acknowledge the supply chain as a
strategic asset achieve 70% higher performance. The "Leaders" in the survey point to next-
generation supply chains, which are fast, flexible, and responsive. They are more concerned
with skills that separate a company from the crowd: 51% say differentiating capabilities is the
real key to success. What additional information would you want to know about the survey
before you accepted the results of the study? - ANS A. What was the margin of error and
sample size?
B. Who funded the study?
C. What sampling design was used?
D. (NOT D)
E. What was the population from which the sample was selected?
F. What was the response rate?
How do the average credit scores of people living in different cities differ? The data in the
accompanying table is an ordered array of the average credit scores of
47 cities. Complete parts (a) through (c) below.
a) Construct a frequency distribution and a percentage distribution that have class intervals
with the upper class boundaries 704, 714, and so on. First construct a frequency distribution.
Then construct a percentage distribution.
b) Construct a cumulative percentage distribution.
c. What conclusions can you reach concerning the average credit scores of people living in
different cities? - ANS c) Most average credit scores are concentrated between 735 and 765.
The following data show the cost of electricity during a summer month for a random sample of
50 one-bedroom apartments in a large city. Use the data to complete parts a through c below.
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QUESTIONS AND CORRECT ANSWERS.
Businesses in a country are listed by size: small, medium, and large. Explain why business size is
an example of an ordinal-scaled variable. - ANS The size of a business is ordinal-scaled
because it has values that can be used as an order or rank of a categorical variable.
Suppose that you measure the time it takes to download a video from the internet.
a. Explain why the download time is a continuous numerical variable.
b. Explain why the download time is a ratio scaled variable. - ANS a) Download time is a
continuous numerical variable because it has numerical values that arise from a measuring
process.
b) Download times are numerical values that imply order and also have a true zero point.
You want to select a random sample of
n=1 from a population of three items (which are called A, B, and C). The rule for selecting the
sample is as follows: Flip a coin; if it is heads, pick item A; if it is tails, flip the coin again; this
time, if it is heads, choose B; if it is tails, choose C. Explain why this is a probability sample but
not a simple random sample. - ANS This is a probability sample because the probability of
each outcome is known, but it is not a simple random sample because there is a higher
probability of picking item A than there is of picking item B or of picking item C.
A hotel management company runs 10 hotels in a resort area. The hotels have a mix of
pricing—some hotels have budget-priced rooms, some have moderate-priced rooms, and some
have deluxe-priced rooms. Data are collected that indicate the number of rooms that are
occupied at each hotel on each day of a month. Explain how the 10 hotels can be recoded into
1 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED
, these three price categories. - ANS Create three new categorical variables, one for each type
of priced room. Determine which hotels include budget-priced rooms and reassign all data for
those hotels to a new categorical variable, budget-priced hotels. Determine which hotels
include moderate-priced rooms and reassign all data for those hotels to a new categorical
variable, moderate-priced hotels. Determine which hotels include deluxe-priced rooms and
reassign all data for those hotels to a new categorical variable, deluxe-priced hotels.
A recent corporate survey indicated that companies that acknowledge the supply chain as a
strategic asset achieve 70% higher performance. The "Leaders" in the survey point to next-
generation supply chains, which are fast, flexible, and responsive. They are more concerned
with skills that separate a company from the crowd: 51% say differentiating capabilities is the
real key to success. What additional information would you want to know about the survey
before you accepted the results of the study? - ANS A. What was the margin of error and
sample size?
B. Who funded the study?
C. What sampling design was used?
D. (NOT D)
E. What was the population from which the sample was selected?
F. What was the response rate?
How do the average credit scores of people living in different cities differ? The data in the
accompanying table is an ordered array of the average credit scores of
47 cities. Complete parts (a) through (c) below.
a) Construct a frequency distribution and a percentage distribution that have class intervals
with the upper class boundaries 704, 714, and so on. First construct a frequency distribution.
Then construct a percentage distribution.
b) Construct a cumulative percentage distribution.
c. What conclusions can you reach concerning the average credit scores of people living in
different cities? - ANS c) Most average credit scores are concentrated between 735 and 765.
The following data show the cost of electricity during a summer month for a random sample of
50 one-bedroom apartments in a large city. Use the data to complete parts a through c below.
2 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED
