The following data-set gives mid-values and frequencies. Calculate its mode.
Mid-value
frequncy
5
7
10
13
15
19
20
24
25
32
30
28
35
17
40
8
45
6
| Mid- value | Class interval | Frequency (f) | Cumulative frequency (c.f) |
| 5 | 2.5-7.5 | 7 | 7 |
| 10 | 7.5-12.5 | 13 | 20 |
| 15 | 12.5-17.5 | 19 | 39 |
| 20 | 17.5-22.5 |  | 63 |
| 25 | 22.5-27.5 |  | 95 |
| 30 | 27.5-32.5 |  | 123 |
| 35 | 32.5-37.5 | 17 | 140 |
| 40 | 37.5-42.5 | 8 | 148 |
| 45 | 42.5-47.5 | 6 | 154 |
By looking at the frequencies, we can say that the mode lies in class interval (22.5 - 27.5).
Therefore, mode is equal to 25.83.