The following table gives the marks obtained by students in the given class interval. Read the table and answer the following questions.
| Class Interval | 0-10 | 10-20 | 20-30 | 30-40 | 40-50 | 50-60 |
| Number of students | 15 | 26 | 35 | 40 | 20 | 14 |
What are the mean marks obtained by the students?
1
30.8
2
32.6
3
29.4
4
34.8