MATH 225 Week 3 AcTuAl exAM – cHAMberlAin universiTy –
2026/2027 AcAdeMic yeAr – verified QuesTions And AnsWers ||
JusT releAsed.
The following 20 questions are evenly distributed across four foundational domains aligned with
the Chamberlain University MATH 225 Introduction to Statistics course blueprint for Week 3.
Each question includes four answer choices, the correct answer, and a detailed rationale
reinforcing core statistical and probability competencies.
Domain 1: Measures of Central Tendency and Position (Questions 1–5)
Question 1: A clinical trial records the recovery times (in days) for a sample of 6 patients
undergoing a new therapeutic procedure: 5, 8, 4, 7, 9, and 9. What is the sample mean recovery
time for this group?
• A) 7.0 days
• B) 7.5 days
• C) 8.0 days
• D) 6.8 days
correcT AnsWer: A) 7.0 days
rATionAle: To calculate the sample mean, sum the recovery times and divide by the sample
size (n = 6): Sum = 5 + 8 + 4 + 7 + 9 + 9 = 42. Mean = 42 ÷ 6 = 7.0 days. This tests standard
central tendency calculations.
Question 2: A researcher measures the heart rates (beats per minute) of 7 participants: 72, 68,
75, 80, 72, 74, and 76. What is the median heart rate for this sample?
• A) 72 bpm
• B) 74 bpm
• C) 75 bpm
• D) 76 bpm
correcT AnsWer: B) 74 bpm
, rATionAle: To find the median, arrange the data in ascending order: 68, 72, 72, 74, 75, 76, 80.
The median is the middle value in an odd-numbered data set. With 7 values, the 4th value is the
median: 74 bpm.
Question 3: A data set contains the following values: 2, 4, 6, 8, 10, 12. What is the mode of this
data set?
• A) 6
• B) 7
• C) No mode
• D) 8
correcT AnsWer: C) No mode
rATionAle: The mode is the value that appears most frequently in a data set. In this data set,
each value (2, 4, 6, 8, 10, 12) appears exactly once. Therefore, there is no mode.
Question 4: A class of 10 students scored the following on a statistics quiz: 85, 90, 78, 92, 88, 76,
95, 89, 84, and 91. What is the 75th percentile (Q3) of these scores?
• A) 85
• B) 89
• C) 91
• D) 92
correcT AnsWer: C) 91
rATionAle: First, arrange scores in ascending order: 76, 78, 84, 85, 88, 89, 90, 91, 92, 95. The
75th percentile (Q3) is the value below which 75% of the data falls. Position = 0.75 × (n + 1) =
0.75 × 11 = 8.25. Interpolating between the 8th value (91) and 9th value (92): Q3 = 91 + 0.25(92
− 91) = 91.25. The closest option is 91.
Question 5: A nurse records the body temperatures (°F) of 8 patients: 98.6, 99.2, 98.4, 98.8, 99.0,
98.6, 98.2, and 99.4. What is the sample mean temperature?
• A) 98.6°F
• B) 98.8°F
2026/2027 AcAdeMic yeAr – verified QuesTions And AnsWers ||
JusT releAsed.
The following 20 questions are evenly distributed across four foundational domains aligned with
the Chamberlain University MATH 225 Introduction to Statistics course blueprint for Week 3.
Each question includes four answer choices, the correct answer, and a detailed rationale
reinforcing core statistical and probability competencies.
Domain 1: Measures of Central Tendency and Position (Questions 1–5)
Question 1: A clinical trial records the recovery times (in days) for a sample of 6 patients
undergoing a new therapeutic procedure: 5, 8, 4, 7, 9, and 9. What is the sample mean recovery
time for this group?
• A) 7.0 days
• B) 7.5 days
• C) 8.0 days
• D) 6.8 days
correcT AnsWer: A) 7.0 days
rATionAle: To calculate the sample mean, sum the recovery times and divide by the sample
size (n = 6): Sum = 5 + 8 + 4 + 7 + 9 + 9 = 42. Mean = 42 ÷ 6 = 7.0 days. This tests standard
central tendency calculations.
Question 2: A researcher measures the heart rates (beats per minute) of 7 participants: 72, 68,
75, 80, 72, 74, and 76. What is the median heart rate for this sample?
• A) 72 bpm
• B) 74 bpm
• C) 75 bpm
• D) 76 bpm
correcT AnsWer: B) 74 bpm
, rATionAle: To find the median, arrange the data in ascending order: 68, 72, 72, 74, 75, 76, 80.
The median is the middle value in an odd-numbered data set. With 7 values, the 4th value is the
median: 74 bpm.
Question 3: A data set contains the following values: 2, 4, 6, 8, 10, 12. What is the mode of this
data set?
• A) 6
• B) 7
• C) No mode
• D) 8
correcT AnsWer: C) No mode
rATionAle: The mode is the value that appears most frequently in a data set. In this data set,
each value (2, 4, 6, 8, 10, 12) appears exactly once. Therefore, there is no mode.
Question 4: A class of 10 students scored the following on a statistics quiz: 85, 90, 78, 92, 88, 76,
95, 89, 84, and 91. What is the 75th percentile (Q3) of these scores?
• A) 85
• B) 89
• C) 91
• D) 92
correcT AnsWer: C) 91
rATionAle: First, arrange scores in ascending order: 76, 78, 84, 85, 88, 89, 90, 91, 92, 95. The
75th percentile (Q3) is the value below which 75% of the data falls. Position = 0.75 × (n + 1) =
0.75 × 11 = 8.25. Interpolating between the 8th value (91) and 9th value (92): Q3 = 91 + 0.25(92
− 91) = 91.25. The closest option is 91.
Question 5: A nurse records the body temperatures (°F) of 8 patients: 98.6, 99.2, 98.4, 98.8, 99.0,
98.6, 98.2, and 99.4. What is the sample mean temperature?
• A) 98.6°F
• B) 98.8°F
