Question

Considers the following distribution of daily wages of $50$ workers of a factory.

Daily wages in Rupees	$200-250$	$250-300$	$300-350$	$350-400$	$400-450$
Number of workers	$6$	$8$	$14$	$10$	$12$

Find the mean daily wages of the workers in the factory by using step-deviation method.

Answer 1

Daily wages	Mean wage	No of workers	Deviation
$200-250$	$225$	$6$	$-100$
$250-300$	$275$	$8$	$-50$
$300-350$	$325=A$	$14$	$0$
$350-400$	$375$	$10$	$50$
$400-450$	$425$	$12$	$100$

Mean $=a+\frac{\sum f_i{d}_i}{\sum f_i}=325+\frac{-100\times 6-50\times 8+14\times 0+10\times 50+12\times 100}{50}$

$=a+\frac{\sum f_i{d}_i}{\sum f_i}=325+\frac{700}{50}=325+14=$ Rs. $339$