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Question
Find the mode of the following frequency distribution.
| Class | 0-10 | 10-20 | 20-30 | 30-40 | 40-50 | 50-60 | 60-70 |
| Frequency | 8 | 10 | 10 | 16 | 12 | 6 | 7 |
Solution
| Class | Frequency |
| 0-10 | 8 |
| 10-20 | 10 |
| 20-30 | 10 →f0 |
| 30-40 | 16 →f1 |
| 40-50 | 12 →f2 |
| 50-60 | 6 |
| 60-70 | 7 |
ere, 30-40 is the modal class and I = 30, h = 10
∴ Mode = I + `((f_0 - f_1)/(2f_1 - f_0 - f_2)) xx "h"`
= 30 + `((16 - 10)/(2xx16-10-12)) xx 10`
= 30 + `16/10xx10 = 30 + 6 = 36`
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