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In a class test, 50 students obtained marks as follows:
| Marks obtained | 0 – 20 | 20 – 40 | 40 – 60 | 60 – 80 | 80 – 100 |
| Number of Students | 4 | 6 | 25 | 10 | 5 |
In a class test, 50 students obtained marks as follows:
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Here the maximum class frequency is 25, and the class corresponding to this frequency is 40-60.
So, the modal class is 40-60.
Now, to find the median class let us put the data in the table given below:
| Marks Obtained | Number of students `(f_i)` | Cumulative frequency (cf) |
| 0-20 | 4 | 4 |
| 20-40 | 6 | 10 |
| 40-60 | 25 | 35 |
| 60-80 | 10 | 45 |
| 80-100 | 5 | 50 |
| Total | `N=Σf_i=50` |
Now, ЁЭСБ=50 тЯ╣`N/2=25.`
The cumulative frequency just greater than 25 is 35, and the corresponding class is 40-60.
Thus, the median class is 40-60.
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