Class-intervals | 10−29 | 30−39 | 40−49 | 50−59 | 59−60 | 60−69 |
Frequencies | 12 | 19 | 20 | 21 | 15 | 13 |
Inclusive Class Interval |
Exclusive Class Interval |
Frequency (f) |
Cumulative Frequency (c.f.) |
10 − 19 20 − 29 |
9.5 − 19.5 19.5 − 29.5 |
12 19 |
12 31 (c.f.) |
30 − 39 | 29.5 − 39.5 | 20 (f) | 51 |
40 − 49 50 − 59 60 − 69 |
39.5 − 49.5 49.5 − 59.5 59.5 − 69.5 |
21 15 13 |
72 87 100 |