,MATH 225N EXAM 1 Statistics | Questions And Answers 2026/2027
Chamberlain
1. A researcher collects data on the number of patients seen per day in a
clinic. Which type of variable is this?
A) Continuous quantitative
B) Discrete quantitative
C) Categorical nominal
D) Categorical ordinal
**Correct Answer:** B) Discrete quantitative
**Rationale:** The number of patients is a numerical (quantitative) variable
that can only take whole-number values (counts). Discrete variables have
gaps between possible values, unlike continuous variables which can take
any value within a range.
2. A nurse records patients' blood types (A, B, AB, O). What level of
measurement is this?
A) Nominal
B) Ordinal
C) Interval
D) Ratio
**Correct Answer:** A) Nominal
**Rationale:** Blood types are categories without any inherent order or
ranking. Nominal data are simply names or labels with no meaningful
numeric relationship. Ordinal data would have a meaningful order, which
blood types do not.
,3. Which of the following is an example of a continuous quantitative
variable?
A) Number of siblings
B) Blood pressure (mmHg)
C) Eye color
D) Pain rating on a 1–10 scale
**Correct Answer:** B) Blood pressure (mmHg)
**Rationale:** Continuous variables can take any value within a range and
can be measured with increasing precision. Blood pressure is measured on a
continuous scale. Number of siblings is discrete, eye color is categorical, and
pain ratings are often treated as ordinal.
4. A study examines the relationship between smoking status (smoker/non-
smoker) and lung function (FEV₁). What type of variable is smoking status?
A) Explanatory, categorical
B) Explanatory, quantitative
C) Response, categorical
D) Response, quantitative
**Correct Answer:** A) Explanatory, categorical
**Rationale:** Smoking status is the explanatory (independent) variable
believed to influence lung function. It is categorical because it places
individuals into groups. The response variable would be FEV₁, which is
quantitative.
5. Which sampling method involves dividing the population into subgroups
and then randomly selecting individuals from each subgroup?
, A) Simple random sampling
B) Stratified sampling
C) Cluster sampling
D) Systematic sampling
**Correct Answer:** B) Stratified sampling
**Rationale:** Stratified sampling divides the population into homogeneous
subgroups (strata) and then draws a random sample from each stratum. This
ensures representation of all subgroups.
6. A researcher selects every 5th patient from a list of clinic patients. 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 start. Selecting every 5th patient fits this definition exactly.
7. A hospital administrator wants to estimate the average length of stay for
patients. She randomly selects 200 patient records from the past year. The
200 records represent:
A) The population
B) The sample
C) The parameter
Chamberlain
1. A researcher collects data on the number of patients seen per day in a
clinic. Which type of variable is this?
A) Continuous quantitative
B) Discrete quantitative
C) Categorical nominal
D) Categorical ordinal
**Correct Answer:** B) Discrete quantitative
**Rationale:** The number of patients is a numerical (quantitative) variable
that can only take whole-number values (counts). Discrete variables have
gaps between possible values, unlike continuous variables which can take
any value within a range.
2. A nurse records patients' blood types (A, B, AB, O). What level of
measurement is this?
A) Nominal
B) Ordinal
C) Interval
D) Ratio
**Correct Answer:** A) Nominal
**Rationale:** Blood types are categories without any inherent order or
ranking. Nominal data are simply names or labels with no meaningful
numeric relationship. Ordinal data would have a meaningful order, which
blood types do not.
,3. Which of the following is an example of a continuous quantitative
variable?
A) Number of siblings
B) Blood pressure (mmHg)
C) Eye color
D) Pain rating on a 1–10 scale
**Correct Answer:** B) Blood pressure (mmHg)
**Rationale:** Continuous variables can take any value within a range and
can be measured with increasing precision. Blood pressure is measured on a
continuous scale. Number of siblings is discrete, eye color is categorical, and
pain ratings are often treated as ordinal.
4. A study examines the relationship between smoking status (smoker/non-
smoker) and lung function (FEV₁). What type of variable is smoking status?
A) Explanatory, categorical
B) Explanatory, quantitative
C) Response, categorical
D) Response, quantitative
**Correct Answer:** A) Explanatory, categorical
**Rationale:** Smoking status is the explanatory (independent) variable
believed to influence lung function. It is categorical because it places
individuals into groups. The response variable would be FEV₁, which is
quantitative.
5. Which sampling method involves dividing the population into subgroups
and then randomly selecting individuals from each subgroup?
, A) Simple random sampling
B) Stratified sampling
C) Cluster sampling
D) Systematic sampling
**Correct Answer:** B) Stratified sampling
**Rationale:** Stratified sampling divides the population into homogeneous
subgroups (strata) and then draws a random sample from each stratum. This
ensures representation of all subgroups.
6. A researcher selects every 5th patient from a list of clinic patients. 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 start. Selecting every 5th patient fits this definition exactly.
7. A hospital administrator wants to estimate the average length of stay for
patients. She randomly selects 200 patient records from the past year. The
200 records represent:
A) The population
B) The sample
C) The parameter
