Question

Class teacher recorded the following absentee record of 30 students of class 9 for the whole year:
Number of absentee 0-10 10-20 20-30 30-40 40-50
Number of students 10 12 5 2 1
Find the mean and the median for the above 
 !!!!!!!!!!!and please do it fast with full elaboration!!!!!!!!!!

Answer 1

No. of absentee    no.of students
0-10                             10
10-20                           12
20-30                            5
30-40                            2
40-50                            1
I am sorry i forgot the formula how to calculate mean and median both