Data Interpretation
1. **Problem 1: Filling tally and frequency for swimming lengths**
- Given responses: 22, 75, 45, 28, 74, 53, 63, 38, 43, 34, 24, 63, 29
- Intervals: 0-24 (A), 25-49 (B), 50-74 (C), 75-99 (D)
- Count frequencies:
- 0-24: 22, 24 → 2 responses
- 25-49: 28, 29, 34, 38, 43, 45 → 6 responses
- 50-74: 53, 63, 63, 74, 75 → 5 responses
- 75-99: 75 → 1 response (75 is in 75-99)
- Tally marks:
- A: ||
- B: ||||||
- C: |||||
- D: |
2. **Problem 2: Completing vehicle sales table**
- Table given:
| | Motorbike | Car | Van | Total |
| Petrol | ? | 2 | 5 | ? |
| Diesel | ? | ? | ? | 11 |
| Electric | 4 | ? | 3 | 9 |
| Total | ? | 10 | ? | 30 |
- Use totals to find missing values:
- Car total = 10, Petrol car = 2, so Electric car = 10 - 2 = 8
- Electric total = 9, Electric motorbike = 4, Electric van = 3, Electric car = 8 (contradiction)
- Sum Electric row: 4 + 8 + 3 = 15, but total given is 9 → inconsistent data
- Conclusion: Cannot complete table with given data; need consistent totals or missing values.
3. **Problem 3: Which tally chart is better?**
- Chart A uses standard tally marks grouped in fives, easy to count.
- Chart B uses stylized tally marks (HH II I), less standard and harder to interpret.
- Better chart: Chart A, because it is clearer and more universally understood.
4. **Problem 4: Fraction of tennis club members aged 30 to 39**
- Total tennis members = 20
- Members aged 30 to 39 = 14
- Fraction = $\frac{14}{20} = \frac{7}{10}$ after simplification.
5. **Problem 5: Drawing tally chart for pet ownership**
- Responses not visible, so cannot draw tally chart.
6. **Problem 6: Games City FC lost**
- Total games City FC played = 35
- Wins = 12
- Draws unknown, but total draws = 40, Town Rovers draws = 8, Club United draws unknown
- Losses City FC = Total games - Wins - Draws
- From table, City FC losses = 35 - 12 - (unknown draws)
- Given total losses for Club United = 7, total games = 90
- Without draws for City FC, cannot find exact losses.
7. **Problem 7: Best use of tally chart**
- A: Height changes each year - continuous data, not suitable.
- B: Favourite music types - categorical data, suitable.
- C: Names of people - nominal data, but tally charts not ideal.
- Best choice: B