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

Let the assume mean A = 17.

We know that mean,

Now, we have.

Putting the values in the above formula, we have

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