MATH 120: INTRODUCTION TO STATISTICS LATEST WEEK 8
FINAL EXAM. MAY QTR WITH 100% ACCURATE ANSWERS.
GRADED A+ (LATEST 2024-2025) WITH RATIONALE
(SMART RATIONALE FOR BETTER UNDERSTANDING)
1. 10 students take an exam and earn the following scores: 86, 96, 90, 92, 79, 94, 86, 74, 82, and 91.
What is the mean of the scores?
• Answer: A: 87
• Explanation: The mean is calculated by adding all the scores and dividing by the total number of
students.
Mean=86+96+90+92+79+94+86+74+82+9110=88010=87\text{Mean} = \frac{86 + 96 + 90 + 92 +
79 + 94 + 86 + 74 + 82 + 91}{10} = \frac{880}{10} =
87Mean=1086+96+90+92+79+94+86+74+82+91=10880=87
2. 10 students take an exam and earn the following scores: 86, 96, 90, 92, 79, 94, 86, 74, 82, and 91.
What is the median of the scores?
• Answer: A: 88
• Explanation: The median is the middle number when the scores are arranged in order.
Sorted scores: 74, 79, 82, 86, 86, 90, 91, 92, 94, 96
Since there are 10 scores, the median is the average of the 5th and 6th scores:
Median=86+902=88\text{Median} = \frac{86 + 90}{2} = 88Median=286+90=88
3. 10 students take an exam and earn the following scores: 86, 96, 90, 92, 79, 94, 86, 74, 82, and 91.
What is the mode of the scores?
• Answer: A: 86
• Explanation: The mode is the score that appears most frequently.
The score 86 appears twice, more than any other score, so it is the mode.
,4. While conducting market research, an automobile manufacturer looks at the number of SUVs and
sedans produced in the prior year. What type of data is this?
• Answer: A: Quantitative data
• Explanation: The data consists of numerical values (number of SUVs and sedans produced), which
is quantitative data.
5. While conducting market research, an automobile manufacturer asks consumers about their
preferences between SUVs and sedans. What type of data is this?
• Answer: A: Qualitative data
• Explanation: The data is about preferences (SUVs vs. sedans), which is categorical and not
numerical, so it is qualitative data.
6. A political think tank wants to conduct a poll of likely voters in a state. If the think tank breaks the
state into 20 groups with common characteristics and then randomly samples each group, what type of
sampling is this?
• Answer: A: Stratified sampling
• Explanation: Stratified sampling involves dividing the population into subgroups (strata) based on
shared characteristics and then sampling randomly from each group.
7. A research team at a medical device manufacturer wants FDA approval for the manufacturer's
latest product. The team sets up a study where half of the participants in the study use the device and
half of the participants in the study do not. When the study is over, the research team compares the
results of the two groups. Which type of study is this?
• Answer: A: Experimental study
, • Explanation: In an experimental study, participants are divided into groups, and an intervention (in
this case, using the device) is applied to one group while the other group is used for comparison.
8. If 10,000 students take a standardized test, which type of graph would be most helpful for
understanding the data?
• Answer: A: A histogram
• Explanation: A histogram is helpful for displaying the distribution of large sets of continuous data,
such as test scores.
9. If the graph is displaying the estimated value of homes in an area, approximately what is the
average home value?
• Answer: A: $375K
• Explanation: The average home value is the mean, which would be approximated based on the data
provided in the graph.
10. Which answer explains why the average home value is above the median home value?
• Answer: A: A few outlier home values are skewing the average high.
• Explanation: Outliers (extremely high or low values) can distort the average, making it higher than
the median, which is less affected by outliers.
FINAL EXAM. MAY QTR WITH 100% ACCURATE ANSWERS.
GRADED A+ (LATEST 2024-2025) WITH RATIONALE
(SMART RATIONALE FOR BETTER UNDERSTANDING)
1. 10 students take an exam and earn the following scores: 86, 96, 90, 92, 79, 94, 86, 74, 82, and 91.
What is the mean of the scores?
• Answer: A: 87
• Explanation: The mean is calculated by adding all the scores and dividing by the total number of
students.
Mean=86+96+90+92+79+94+86+74+82+9110=88010=87\text{Mean} = \frac{86 + 96 + 90 + 92 +
79 + 94 + 86 + 74 + 82 + 91}{10} = \frac{880}{10} =
87Mean=1086+96+90+92+79+94+86+74+82+91=10880=87
2. 10 students take an exam and earn the following scores: 86, 96, 90, 92, 79, 94, 86, 74, 82, and 91.
What is the median of the scores?
• Answer: A: 88
• Explanation: The median is the middle number when the scores are arranged in order.
Sorted scores: 74, 79, 82, 86, 86, 90, 91, 92, 94, 96
Since there are 10 scores, the median is the average of the 5th and 6th scores:
Median=86+902=88\text{Median} = \frac{86 + 90}{2} = 88Median=286+90=88
3. 10 students take an exam and earn the following scores: 86, 96, 90, 92, 79, 94, 86, 74, 82, and 91.
What is the mode of the scores?
• Answer: A: 86
• Explanation: The mode is the score that appears most frequently.
The score 86 appears twice, more than any other score, so it is the mode.
,4. While conducting market research, an automobile manufacturer looks at the number of SUVs and
sedans produced in the prior year. What type of data is this?
• Answer: A: Quantitative data
• Explanation: The data consists of numerical values (number of SUVs and sedans produced), which
is quantitative data.
5. While conducting market research, an automobile manufacturer asks consumers about their
preferences between SUVs and sedans. What type of data is this?
• Answer: A: Qualitative data
• Explanation: The data is about preferences (SUVs vs. sedans), which is categorical and not
numerical, so it is qualitative data.
6. A political think tank wants to conduct a poll of likely voters in a state. If the think tank breaks the
state into 20 groups with common characteristics and then randomly samples each group, what type of
sampling is this?
• Answer: A: Stratified sampling
• Explanation: Stratified sampling involves dividing the population into subgroups (strata) based on
shared characteristics and then sampling randomly from each group.
7. A research team at a medical device manufacturer wants FDA approval for the manufacturer's
latest product. The team sets up a study where half of the participants in the study use the device and
half of the participants in the study do not. When the study is over, the research team compares the
results of the two groups. Which type of study is this?
• Answer: A: Experimental study
, • Explanation: In an experimental study, participants are divided into groups, and an intervention (in
this case, using the device) is applied to one group while the other group is used for comparison.
8. If 10,000 students take a standardized test, which type of graph would be most helpful for
understanding the data?
• Answer: A: A histogram
• Explanation: A histogram is helpful for displaying the distribution of large sets of continuous data,
such as test scores.
9. If the graph is displaying the estimated value of homes in an area, approximately what is the
average home value?
• Answer: A: $375K
• Explanation: The average home value is the mean, which would be approximated based on the data
provided in the graph.
10. Which answer explains why the average home value is above the median home value?
• Answer: A: A few outlier home values are skewing the average high.
• Explanation: Outliers (extremely high or low values) can distort the average, making it higher than
the median, which is less affected by outliers.
