Question

A class teacher has the following absentee record of 40 students of a

class for the whole term. Find the mean number of days a student was

absent.

Number of days 0-6 6-10 10-14 14-20 20-28 28-38 38-40

Number of students 11 10 7 4 4 3 1​

Answer 1

Sum of Number of students/ Sum of terms

40/ 7

= 5.714 students were absent in mean.

Answer 2

Answer

Answer:-

No. of days No. of ststud

0-6 11 3 33

6 - 10 10 8 80

10 - 14 7 12 84

14 - 20 4 17 68

20 - 28 4 24 96

28 - 38 3 33 99

38 - 40 1 39 39

Σf

i

=40 Σf

i

x

i

=499

The mean number of days a student was absent =

Σf

i

Σf

i

x

i

=

40

499

=12.475

Hence, the mean number of days a student was absent is 12.475.