Mathematics
The mean of the following distribution is 50. Find the unknown frequency.
| Class Interval | Frequency |
|---|---|
| 0 - 20 | 6 |
| 20 - 40 | f |
| 40 - 60 | 8 |
| 60 - 80 | 12 |
| 80 - 100 | 8 |
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