Answer:
mode is {15-20) as it has high frequency.
class x frequency F. CF
5-10. 5. 5
10-15. 7. 12
15-20. 11. 23
20-25. 8. 31
25-30. 10. 41
30-35. 3. 44
35-40. 2. 46
N=46
median =(N/2)th term =46/2=23 th term
in CF column just equal to 23 is 23
median class =(15-20)
median =15+ (23-12)/11×5=20