Question

The following distribution gives the number of accidents met by 160 workers in a factory during a month.

No. of accidents (x):	0	1	2	3	4
No. of workers (f):	70	52	34	3	1

Find the average number of accidents per worker.

Answer 1

Let the assumed mean (A) = 2

No. of accidents (xi)	No. of workers (fi)	ui = xi - A = xi - 2	fiui
0	70	-2	-140
1	52	-1	-52
2	34	0	0
3	3	1	3
4	1	2	2
	N = 160		\(\sum\)fiui = -187

Average number of accidents per day workers = A + \(\frac{\sum f_iu_i}{N}\)

\(=2+(-\frac{187}{160})=\frac{320-187}{160}\)

\(=0.83\)