| Class | 0 5 | 5 10 | 10 15 | 15 20 | 20 25 |
| Frequency | 10 | 15 | 12 | 20 | 9 |
the sum of lower limits of the median class and modal class is 25.
Explanation:
| Class | Frequency | Cumulative Frequency |
| 0 5 | 10 | 10 |
| 5 10 | 15 | 25 |
| 10 15 | 12 | 37 |
| 15 20 | 20 | 57 |
| 20 25 | 9 | 66 |
From the table, $N/2 = 66/2 = 33$
Which **** in the interval 10 15.
Hence, lower limit of the median class is 10.
The highest frequency is 20, which **** in between the interval 15 20.
Hence, lower limit of modal class is 15.
Therefore, required sum is 10 + 15 = 25.
