ERB Data Analysis and Statistics 1 — Questions and Answers
Question 1: A class of 10 students scored the following on a quiz: 72, 85, 90, 68, 75, 88, 92, 78, 85, 67. What is the mean score?
- 80 (Correct answer)
- 78
- 85
- 82
Correct answer: 80
The mean is the sum of all scores (800) divided by the number of students (10), which equals 80.
Question 2: In a data set of seven numbers arranged in order — 4, 7, 9, 12, 15, 18, 22 — what is the median?
- 9
- 12 (Correct answer)
- 15
- 11
Correct answer: 12
The median is the middle value when data is ordered; with 7 values, the 4th value (12) is the middle.
Question 3: A survey asked 40 students their favorite subject. Results: Math 12, Science 8, English 10, History 10. What percentage chose Math?
- 25%
- 30% (Correct answer)
- 20%
- 12%
Correct answer: 30%
12 out of 40 students chose Math; 12/40 = 0.30, which equals 30%.
Question 4: A line graph shows a city's average temperature rising from 30°F in January to 85°F in July, then falling back to 35°F in December. Which conclusion is best supported?
- The city has a tropical climate
- The city experiences seasonal temperature variation (Correct answer)
- July is always the hottest month in every city
- Temperatures never drop below freezing
Correct answer: The city experiences seasonal temperature variation
The data shows temperatures rising and falling across the year, which is characteristic of seasonal variation.
Question 5: What is the range of the data set: 14, 27, 8, 33, 19, 45, 6?
- 39 (Correct answer)
- 27
- 33
- 45
Correct answer: 39
Range is the difference between the maximum (45) and minimum (6) values: 45 − 6 = 39.
Question 6: A bar graph shows book sales for four genres: Mystery 120, Romance 95, Science Fiction 80, Biography 105. Which genre had the second-highest sales?
- Mystery
- Romance
- Biography (Correct answer)
- Science Fiction
Correct answer: Biography
Ordering from highest to lowest: Mystery (120), Biography (105), Romance (95), Science Fiction (80) — Biography is second.
Question 7: In the data set 3, 7, 7, 9, 11, 14, 7, what is the mode?
- 7 (Correct answer)
- 9
- 3
- 11
Correct answer: 7
The mode is the value that appears most often; 7 appears three times, more than any other value.
ERB Data Analysis and Statistics 1
A class of 10 students scored the following on a quiz: 72, 85, 90, 68, 75, 88, 92, 78, 85, 67.
What is the mean score?