QBA COBA CORE EXAM 2025
QUESTIONS AND ANSWERS
Which of the following is a discrete quantitative (numerical) variable?
a) The Dow Jones Industrial average
b) The volume of water released from a dam
c) The distance you drove yesterday.
d) The number of employees of an insurance company - ANS d) The number of employees of
an insurance company
Which of the following is a continuous quantitative (numerical) variable?
a) The color of a student's eyes
b) The number of employees of an insurance company
c) The amount of milk in a 2-liter carton.
d) The number of gallons of milk sold at the local grocery store yesterday - ANS c) The
amount of milk in a 2-liter carton
To monitor campus security, the campus police office is taking a survey of the number of
students in a parking lot each 30 minutes of a 24-hour period with the goal of determining
when patrols of the lot would serve the most students. If X is the number of students in the lot
each period of time, then X is an example of
a) a categorical variable
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,b) a discrete variable
c) a continuous variable
d) a statistic - ANS b) a discrete variable
Researchers are concerned that the weight of the average American school child is increasing
implying, among other things, that children's clothing should be manufactured and marketed in
larger sizes. If X is the weight of school children sampled in a nationwide study, then X is an
example of
a) a categorical variable
b) a discrete variable
c) a continuous variable
d) a table of random numbers - ANS c) a continuous variable
The chancellor of a major university was concerned about alcohol abuse on campus and
wanted to find out the proportion of students at the university who visited campus bars on the
weekend before the final exam week. A random sample of 250 students was taken. The answer
on "whether you visited campus bars on the weekend before the final exam week" from
students in the sample is an example of .
a) a categorical variable
b) a discrete variable
c) a continuous variable
d) a table of random numbers - ANS a) a categorical variable
The portion of the universe that has been selected for analysis is called
a) a sample
b) a frame
c) a primary data source
d) a secondary data source - ANS a) sample
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, Which of the following is most likely a population as opposed to a sample?
a) respondents to a newspaper survey
b) the first 5 students completing an assignment
c) every third person to arrive at the bank
d) registered voters in a county - ANS d) registered voters in a country
A study is underway in Yosemite National Forest to determine the adult height of American
pine trees. Specifically, the study is attempting to determine what factors aid a tree in reaching
heights greater than 60 feet tall. It is estimated that the forest contains 25,000 adult American
pines. The study involves collecting heights from 250 randomly selected adult American pine
trees and analyzing the results. Identify the population from which the study was sampled.
a) The 250 randomly selected adult American pine trees
b) The 25,000 adult American pine trees in the forest
c) All the adult American pine trees taller than 60 feet
d) All American pine trees, of any age, in the forest - ANS b) the 25,000 adult American pine
trees in the forest
A study is under way in Yosemite National Forest to determine the adult height of American
pine trees. Specifically, the study is attempting to determine what factors aid a tree in reaching
heights greater than 60 feet tall. It is estimated that the forest contains 25,000 adult American
pines. The study involves collecting heights from 250 randomly selected adult American pine
trees and analyzing the results. Identify the sample in the study.
a) The 250 randomly selected adult American pine trees
b) The 25,000 adult American pine trees in the forest
c) All the adult American pine trees taller than 60 feet
d) All American pine trees, of any age, in the forest - ANS a) The 250 randomly selected adult
American pine trees
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QUESTIONS AND ANSWERS
Which of the following is a discrete quantitative (numerical) variable?
a) The Dow Jones Industrial average
b) The volume of water released from a dam
c) The distance you drove yesterday.
d) The number of employees of an insurance company - ANS d) The number of employees of
an insurance company
Which of the following is a continuous quantitative (numerical) variable?
a) The color of a student's eyes
b) The number of employees of an insurance company
c) The amount of milk in a 2-liter carton.
d) The number of gallons of milk sold at the local grocery store yesterday - ANS c) The
amount of milk in a 2-liter carton
To monitor campus security, the campus police office is taking a survey of the number of
students in a parking lot each 30 minutes of a 24-hour period with the goal of determining
when patrols of the lot would serve the most students. If X is the number of students in the lot
each period of time, then X is an example of
a) a categorical variable
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,b) a discrete variable
c) a continuous variable
d) a statistic - ANS b) a discrete variable
Researchers are concerned that the weight of the average American school child is increasing
implying, among other things, that children's clothing should be manufactured and marketed in
larger sizes. If X is the weight of school children sampled in a nationwide study, then X is an
example of
a) a categorical variable
b) a discrete variable
c) a continuous variable
d) a table of random numbers - ANS c) a continuous variable
The chancellor of a major university was concerned about alcohol abuse on campus and
wanted to find out the proportion of students at the university who visited campus bars on the
weekend before the final exam week. A random sample of 250 students was taken. The answer
on "whether you visited campus bars on the weekend before the final exam week" from
students in the sample is an example of .
a) a categorical variable
b) a discrete variable
c) a continuous variable
d) a table of random numbers - ANS a) a categorical variable
The portion of the universe that has been selected for analysis is called
a) a sample
b) a frame
c) a primary data source
d) a secondary data source - ANS a) sample
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, Which of the following is most likely a population as opposed to a sample?
a) respondents to a newspaper survey
b) the first 5 students completing an assignment
c) every third person to arrive at the bank
d) registered voters in a county - ANS d) registered voters in a country
A study is underway in Yosemite National Forest to determine the adult height of American
pine trees. Specifically, the study is attempting to determine what factors aid a tree in reaching
heights greater than 60 feet tall. It is estimated that the forest contains 25,000 adult American
pines. The study involves collecting heights from 250 randomly selected adult American pine
trees and analyzing the results. Identify the population from which the study was sampled.
a) The 250 randomly selected adult American pine trees
b) The 25,000 adult American pine trees in the forest
c) All the adult American pine trees taller than 60 feet
d) All American pine trees, of any age, in the forest - ANS b) the 25,000 adult American pine
trees in the forest
A study is under way in Yosemite National Forest to determine the adult height of American
pine trees. Specifically, the study is attempting to determine what factors aid a tree in reaching
heights greater than 60 feet tall. It is estimated that the forest contains 25,000 adult American
pines. The study involves collecting heights from 250 randomly selected adult American pine
trees and analyzing the results. Identify the sample in the study.
a) The 250 randomly selected adult American pine trees
b) The 25,000 adult American pine trees in the forest
c) All the adult American pine trees taller than 60 feet
d) All American pine trees, of any age, in the forest - ANS a) The 250 randomly selected adult
American pine trees
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