(Q4). The table below gives the percentage distribution of female teachers in the primary schools of rural areas of various states and union territories (U.T.) of India. Find the mean percentage of female teachers using all the three methods.

Percentage of female teachers	15-25	25-35	35-45	45-55	55-65	65-75	75-85
Number of States/U.T	6	11	7	4	4	2	1

Solution : Let us find the class marks x_i of each class, and arrange them in a table.

Here, we take a=50 and h=10.

Now find d_i and u_i and write them in the table

Percentage of female teachers C.I	Number of States/U.T. fi	xi	di = xi - 50	ui = xi - 50 10	fixi	fidi	fiui
15-25	6	20	-	-		-	-
25-35	11	30	-	-		-	-
35-45	7	40	-	-		-	-
45-55	4	50
55-65	4	60
65-75	2	70
75-85	1	80
Total	35	-	-	-		-	-

From the above table, we obtain ∑f_i = 35, ∑f_ix_i = , ∑f_id_i = -, ∑f_iu_i = -

Therefore, the mean percentage of female teachers in the primary schools of rural areas is .71