Find mean by direct method
Dear Student
Mean = ∑fm/∑f = 1420/40 = 35.5
Regards
| Marks | f | M | fM | |
|---|---|---|---|---|
| 10-19 | 9.5-19.5 | 5 | 14.5 | 72.5 |
| 20-29 | 19.5-29.5 | 8 | 24.5 | 196 |
| 30-39 | 29.5-39.5 | 12 | 34.5 | 414 |
| 40-49 | 39.5-49.5 | 8 | 44.5 | 356 |
| 50-59 | 49.5-59.5 | 7 | 54.5 | 381.5 |
| 40 | 1420 |
Mean = ∑fm/∑f = 1420/40 = 35.5
Regards