Question

Frequency distribution of daily commission received by 100 salesmen is given below :

Daily Commission (in Rs.)	No. of Salesmen
100-120	20
120-140	45
140-160	22
160-180	09
180-200	04

Find mean daily commission received by salesmen, by the assumed mean method.

Answer 1

Daily commission	Classmark	`d_i = x_i - A` `d_i = x_i - 150`	No. of salemen `F_i`	`f_id_i`
100 120	110	-40	20	-800
120 140	130	-20	45	-900
140 160	150→A	0	22	0
160 180	170	20	09	180
180 200	190	40	04	160
			`sumf_i = 100`	`sumf_ix_i = -1360`

`bard = (sumf_id_i)/(sumf)` = `1360/100 = -13.60`

`:. barx = A + bard = 150 + (-13.60) = 136.4`