CHSPE Data Analysis 3 — Questions and Answers
Question 1: A stem-and-leaf plot has stems 2, 3, 4 with leaves 2|5, 3|1 4 7, 4|0 2. What is the largest value in the data set?
- 42 (Correct answer)
- 47
- 40
- 37
Correct answer: 42
The stem 4 with leaf 2 gives the value 42, which is the largest value shown.
Question 2: Which of the following best describes a sample that is representative of a population?
- It includes only the most extreme values
- It reflects the diversity of the whole population (Correct answer)
- It is always larger than the population
- It uses only voluntary responses
Correct answer: It reflects the diversity of the whole population
A representative sample reflects the characteristics of the overall population, allowing valid generalizations.
Question 3: Data set: 3, 5, 5, 7, 9, 9, 9. What is the mode?
- 5
- 7
- 9 (Correct answer)
- 3
Correct answer: 9
The mode is 9 because it appears three times, more than any other value.
Question 4: A histogram shows most data clustered on the right side with a long tail extending to the left. This distribution is called:
- Symmetric
- Left-skewed (Correct answer)
- Right-skewed
- Uniform
Correct answer: Left-skewed
When the tail points to the left (lower values), the distribution is left-skewed (negatively skewed).
Question 5: If the probability of rain tomorrow is 0.35, what is the probability it will NOT rain?
- 0.35
- 0.50
- 0.65 (Correct answer)
- 0.70
Correct answer: 0.65
Complementary probability: 1 − 0.35 = 0.65.
Question 6: A class has test scores: 70, 75, 80, 85, 90. If a score of 50 is added, which measure changes the LEAST?
- Mean
- Median (Correct answer)
- Range
- Mode
Correct answer: Median
Adding one low outlier shifts the mean significantly and increases the range, but the median changes only slightly.
Question 7: A pie chart shows that 30% of a school budget goes to sports. If the total budget is $500,000, how much goes to sports?
- $15,000
- $30,000
- $150,000 (Correct answer)
- $300,000
Correct answer: $150,000
30% of $500,000 = 0.30 × 500,000 = $150,000.
CHSPE Data Analysis 3
A stem-and-leaf plot has stems 2, 3, 4 with leaves 2|5, 3|1 4 7, 4|0 2.
What is the largest value in the data set?