,MATH 225N Final EXAM Statistics | Questions And Answers
2026/2027 Chamberlain
1. A researcher is studying the average recovery time (in days) for patients
after a specific surgery. Recovery time can be 5.2 days, 6.8 days, or any
value in between. Which classification best describes this variable?
A) Discrete quantitative
B) Continuous quantitative
C) Categorical nominal
D) Categorical ordinal
**Correct Answer:** B) Continuous quantitative
**Rationale:** Recovery time measured in days can take any value within a
range (including fractions), making it continuous. Discrete variables take only
countable whole-number values. Categorical variables represent categories,
not numerical measurements.
2. A nurse records patients' education levels as "High School," "Associate's,"
"Bachelor's," and "Graduate." What is the highest level of measurement for
this variable?
A) Nominal
B) Ordinal
C) Interval
D) Ratio
**Correct Answer:** B) Ordinal
**Rationale:** Education levels have a meaningful order (High School <
Associate's < Bachelor's < Graduate), but the intervals between categories
,are not necessarily equal. This makes it ordinal data, not nominal (no order)
or interval/ratio (equal intervals).
3. Which sampling method divides the population into groups based on a
characteristic and then randomly selects individuals from each group in
proportion to their representation in the population?
A) Simple random sampling
B) Stratified sampling
C) Cluster sampling
D) Systematic sampling
**Correct Answer:** B) Stratified sampling
**Rationale:** Stratified sampling ensures representation of subgroups by
dividing the population into strata (e.g., by age or gender) and randomly
sampling from each. Cluster sampling divides into groups but randomly
selects entire clusters, not individuals from each.
4. A hospital administrator selects every 10th patient from an alphabetical
list of all discharged patients to survey about satisfaction. This is an example
of:
A) Simple random sampling
B) Stratified sampling
C) Cluster sampling
D) Systematic sampling
**Correct Answer:** D) Systematic sampling
**Rationale:** Systematic sampling selects every kth element from a list
after a random starting point. Selecting every 10th patient from an ordered
, list fits this definition precisely. Simple random sampling would require each
patient to have an equal independent chance of selection.
5. The average age of all patients admitted to a hospital last year is 58.4
years. This value is a:
A) Statistic
B) Parameter
C) Sample
D) Variable
**Correct Answer:** B) Parameter
**Rationale:** A parameter is a numerical summary of a population (all
patients admitted). A statistic describes a sample (a subset). Since this
average describes the entire population of admitted patients, it is a
parameter.
6. A researcher computes the mean, median, and standard deviation of a
dataset. This is an example of:
A) Inferential statistics
B) Descriptive statistics
C) Probability
D) Hypothesis testing
**Correct Answer:** B) Descriptive statistics
**Rationale:** Descriptive statistics summarize and describe the features of
a dataset through measures of central tendency (mean, median) and spread
(standard deviation). Inferential statistics use sample data to draw
conclusions about populations.
2026/2027 Chamberlain
1. A researcher is studying the average recovery time (in days) for patients
after a specific surgery. Recovery time can be 5.2 days, 6.8 days, or any
value in between. Which classification best describes this variable?
A) Discrete quantitative
B) Continuous quantitative
C) Categorical nominal
D) Categorical ordinal
**Correct Answer:** B) Continuous quantitative
**Rationale:** Recovery time measured in days can take any value within a
range (including fractions), making it continuous. Discrete variables take only
countable whole-number values. Categorical variables represent categories,
not numerical measurements.
2. A nurse records patients' education levels as "High School," "Associate's,"
"Bachelor's," and "Graduate." What is the highest level of measurement for
this variable?
A) Nominal
B) Ordinal
C) Interval
D) Ratio
**Correct Answer:** B) Ordinal
**Rationale:** Education levels have a meaningful order (High School <
Associate's < Bachelor's < Graduate), but the intervals between categories
,are not necessarily equal. This makes it ordinal data, not nominal (no order)
or interval/ratio (equal intervals).
3. Which sampling method divides the population into groups based on a
characteristic and then randomly selects individuals from each group in
proportion to their representation in the population?
A) Simple random sampling
B) Stratified sampling
C) Cluster sampling
D) Systematic sampling
**Correct Answer:** B) Stratified sampling
**Rationale:** Stratified sampling ensures representation of subgroups by
dividing the population into strata (e.g., by age or gender) and randomly
sampling from each. Cluster sampling divides into groups but randomly
selects entire clusters, not individuals from each.
4. A hospital administrator selects every 10th patient from an alphabetical
list of all discharged patients to survey about satisfaction. This is an example
of:
A) Simple random sampling
B) Stratified sampling
C) Cluster sampling
D) Systematic sampling
**Correct Answer:** D) Systematic sampling
**Rationale:** Systematic sampling selects every kth element from a list
after a random starting point. Selecting every 10th patient from an ordered
, list fits this definition precisely. Simple random sampling would require each
patient to have an equal independent chance of selection.
5. The average age of all patients admitted to a hospital last year is 58.4
years. This value is a:
A) Statistic
B) Parameter
C) Sample
D) Variable
**Correct Answer:** B) Parameter
**Rationale:** A parameter is a numerical summary of a population (all
patients admitted). A statistic describes a sample (a subset). Since this
average describes the entire population of admitted patients, it is a
parameter.
6. A researcher computes the mean, median, and standard deviation of a
dataset. This is an example of:
A) Inferential statistics
B) Descriptive statistics
C) Probability
D) Hypothesis testing
**Correct Answer:** B) Descriptive statistics
**Rationale:** Descriptive statistics summarize and describe the features of
a dataset through measures of central tendency (mean, median) and spread
(standard deviation). Inferential statistics use sample data to draw
conclusions about populations.
