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COBA CORE: QBA Questions with
Detailed Verified Answers
Which of the following is a discrete quantitative (numerical)
variable? Ans: The number of employees of an insurance
company
Which of the following is a continuous quantitative (numerical)
variable? Ans: 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 Ans: 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 Ans: A continuous
variable
The chancellor of a major university was concerned about alcohol
abuse on her campus and wanted to find out the proportion of
students at her university who visited campus bars on the
weekend before the final exam week. Her assistant took a random
sample of 250 students. The answer on "whether you visited
campus bars on the weekend before the final exam week" from
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students in the sample is an example of Ans: a categorical
variable
The portion of the universe that has been selected for analysis is
called Ans: a sample
Which of the following is most likely a population as opposed to a
sample?` Ans: registered voters in a country
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 population from
which the study was sampled. Ans: 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. Ans: The 250 randomly selected adult American pine trees.
Most analysts focus on the cost of tuition and the way to measure
the cost of a college education. But incidentals, such as textbook
costs, are rarely considered. A researcher at Drummand University
wishes to estimate the textbook costs of first-year students
Drummand. To do so, she monitored the textbook cost of 250 first-
COBA CORE: QBA Questions with
Detailed Verified Answers
Which of the following is a discrete quantitative (numerical)
variable? Ans: The number of employees of an insurance
company
Which of the following is a continuous quantitative (numerical)
variable? Ans: 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 Ans: 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 Ans: A continuous
variable
The chancellor of a major university was concerned about alcohol
abuse on her campus and wanted to find out the proportion of
students at her university who visited campus bars on the
weekend before the final exam week. Her assistant took a random
sample of 250 students. The answer on "whether you visited
campus bars on the weekend before the final exam week" from
, Page | 2
students in the sample is an example of Ans: a categorical
variable
The portion of the universe that has been selected for analysis is
called Ans: a sample
Which of the following is most likely a population as opposed to a
sample?` Ans: registered voters in a country
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 population from
which the study was sampled. Ans: 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. Ans: The 250 randomly selected adult American pine trees.
Most analysts focus on the cost of tuition and the way to measure
the cost of a college education. But incidentals, such as textbook
costs, are rarely considered. A researcher at Drummand University
wishes to estimate the textbook costs of first-year students
Drummand. To do so, she monitored the textbook cost of 250 first-
