Question
Write the median class for the following frequency distribution:
| Class-interval | 0-10 | 10-20 | 20-30 | 30-40 | 40-50 | 50-60 | 60-70 | 70-80 |
| Frequency | 5 | 8 | 7 | 12 | 28 | 20 | 10 | 10 |
