STATISTICS REVISION QUESTIONS

A. Data Handling & Collection

1. Define the term “statistics” in your own words.
2. What is the difference between primary and secondary data?
3. List three methods used to collect data in statistics.
4. A survey was conducted in a school to find students' favorite sport. What type of data is this: qualitative or quantitative?
5. State one advantage and one disadvantage of using a questionnaire to collect data.

6. The following are ages (in years) of 10 students: 14, 15, 15, 16, 14, 15, 17, 16, 14, 15.
   Present this data using a frequency table.
7. What type of graph is best for showing the distribution of marks in a test?
8. What is a histogram, and how is it different from a bar chart?
9. Draw a pie chart to represent the following data:
   - Math: 30%
   - Science: 20%
   - English: 25%
   - History: 25%
10. Explain why a line graph is useful when showing change over time.

C. Measures of Central Tendency

11. Find the mean of the following numbers: 5, 10, 15, 20, 25.
12. What is the median of these values: 3, 8, 2, 7, 6?
13. Determine the mode of the set: 4, 6, 4, 7, 4, 6, 5.
14. Explain when it is more appropriate to use the median instead of the mean.
15. Calculate the mean from the frequency table:
    Value: 1 | 2 | 3
    Freq: 3 | 4 | 3

D. Measures of Dispersion and Probability

16. Define the term “range” in statistics and find the range of 9, 12, 15, 18, 21.
17. If a die is rolled, what is the probability of getting an even number?
18. A box contains 4 red, 3 green, and 5 blue balls. One is picked at random. What is the probability it is not green?
19. Explain what is meant by the term “probability” and give one real-life example.
20. The heights (in cm) of five students are: 150, 160, 170, 160, 160. Find the mode and mean height.