WGU D772 Statistical Data Literacy
OA: Practice Questions with Detailed
Rationales – Complete Exam Prep
Question 1
What is a population in statistical research?
A) A smaller group selected from a larger group
B) The entire group of individuals or objects that you want to study
C) A numerical value calculated from sample data
D) The actual values collected in a study
Correct Answer: B
Rationale: A population is the complete collection of all individuals, items,
or data points of interest in a study. It represents the entire group
researchers want to draw conclusions about. Studying an entire population
is often impractical, which is why samples are used instead .
Question 2
What is a sample in statistical research?
,A) The entire group of individuals or objects being studied
B) A smaller, more manageable group selected from the population to
represent the larger group
C) A numerical value that describes a population characteristic
D) The actual values of the variables collected
Correct Answer: B
Rationale: A sample is a subset of the population selected for study.
Researchers use samples because studying an entire population is often
impractical or impossible due to time, cost, or accessibility constraints .
Question 3
Which of the following is an example of a parameter?
A) The average height of 100 adult women randomly selected from the
United States
B) The average height of all adult women in the United States
C) The number of patients in a clinical trial
D) The sample mean of a study
Correct Answer: B
Rationale: A parameter is a numerical value describing an entire
population's characteristics. The average height of all adult women in the
United States describes the entire population, making it a parameter. In
contrast, a statistic describes a sample .
,Question 4
Which of the following is an example of a statistic?
A) The average height of all adult women in the United States
B) The average height of 100 adult women randomly selected from the
United States
C) The total population of a city
D) The actual population mean
Correct Answer: B
Rationale: A statistic is a numerical value that describes a characteristic of a
sample. The average height of 100 randomly selected adult women is
calculated from sample data, making it a statistic used to estimate the
population parameter .
Question 5
What three basic elements make up a dataset?
A) Samples, populations, and parameters
B) Individuals, variables, and data
C) Statistics, parameters, and errors
D) Means, medians, and modes
Correct Answer: B
Rationale: A dataset consists of three basic elements: individuals (the
objects being studied), variables (the characteristics measured), and data
, (the actual values collected). These elements form the foundation of any
statistical analysis .
Question 6
Which of the following is a quantitative variable?
A) Hair color
B) Occupation
C) Age
D) Favorite food
Correct Answer: C
Rationale: Quantitative variables are numerical measurements, such as age,
height, weight, or income. These variables represent quantities that can be
measured and analyzed mathematically. Hair color, occupation, and favorite
food are categorical variables .
Question 7
Which of the following is a categorical variable?
A) Height in inches
B) Weight in pounds
C) Blood type
D) Temperature in degrees
Correct Answer: C
OA: Practice Questions with Detailed
Rationales – Complete Exam Prep
Question 1
What is a population in statistical research?
A) A smaller group selected from a larger group
B) The entire group of individuals or objects that you want to study
C) A numerical value calculated from sample data
D) The actual values collected in a study
Correct Answer: B
Rationale: A population is the complete collection of all individuals, items,
or data points of interest in a study. It represents the entire group
researchers want to draw conclusions about. Studying an entire population
is often impractical, which is why samples are used instead .
Question 2
What is a sample in statistical research?
,A) The entire group of individuals or objects being studied
B) A smaller, more manageable group selected from the population to
represent the larger group
C) A numerical value that describes a population characteristic
D) The actual values of the variables collected
Correct Answer: B
Rationale: A sample is a subset of the population selected for study.
Researchers use samples because studying an entire population is often
impractical or impossible due to time, cost, or accessibility constraints .
Question 3
Which of the following is an example of a parameter?
A) The average height of 100 adult women randomly selected from the
United States
B) The average height of all adult women in the United States
C) The number of patients in a clinical trial
D) The sample mean of a study
Correct Answer: B
Rationale: A parameter is a numerical value describing an entire
population's characteristics. The average height of all adult women in the
United States describes the entire population, making it a parameter. In
contrast, a statistic describes a sample .
,Question 4
Which of the following is an example of a statistic?
A) The average height of all adult women in the United States
B) The average height of 100 adult women randomly selected from the
United States
C) The total population of a city
D) The actual population mean
Correct Answer: B
Rationale: A statistic is a numerical value that describes a characteristic of a
sample. The average height of 100 randomly selected adult women is
calculated from sample data, making it a statistic used to estimate the
population parameter .
Question 5
What three basic elements make up a dataset?
A) Samples, populations, and parameters
B) Individuals, variables, and data
C) Statistics, parameters, and errors
D) Means, medians, and modes
Correct Answer: B
Rationale: A dataset consists of three basic elements: individuals (the
objects being studied), variables (the characteristics measured), and data
, (the actual values collected). These elements form the foundation of any
statistical analysis .
Question 6
Which of the following is a quantitative variable?
A) Hair color
B) Occupation
C) Age
D) Favorite food
Correct Answer: C
Rationale: Quantitative variables are numerical measurements, such as age,
height, weight, or income. These variables represent quantities that can be
measured and analyzed mathematically. Hair color, occupation, and favorite
food are categorical variables .
Question 7
Which of the following is a categorical variable?
A) Height in inches
B) Weight in pounds
C) Blood type
D) Temperature in degrees
Correct Answer: C
