Question

The scores of a batsman in 8 innings are given as 48, 40, 36, 35, 46, 42, 36 and 37.

Find (i) Average score (ii) Variance and (iii) Standard Deviation of scores.

Answer 1

Table of calculation
Observation X	Deviation	Square of Deviation D2
48	8	64
40	0	0
36	–4	16
35	–5	25
46	6	36
42	2	4
36	–4	16
37	– 3	9
= 320		= 170

Number of observation = N = 8

(i) Mean = = = 40

∴ Average score of a batsman = 40

(ii) Variance, = = 21.25

(iii)

On an average, the individual observations deviate from the arithmetic mean by 4.61.