The following results show the number of workers and the wages paid to them in two factories A and B of the same industry.

(i) Which firm pays a larger amount as monthly wages?


(ii) Which firm shows greater variability in individual wages?


(i) Both the factories pay the same mean monthly wages.


For factory A there are 560 workers. And for factory B there are 650 workers.


So, factory A totally pays as monthly wage = (5460 x 560) Rs.


= 3057600 Rs.


Factory B totally pays as monthly wage = (5460 x 650) Rs.


= 3549000 Rs.


That means, factory B pays a larger amount as monthly wages.


(ii) Mean wages of both the factories are the same, i.e., Rs. 5460.


To compare variation, we need to find out the coefficient of variation (CV).


We know, CV = , where SD is the standard deviation.


The variance of factory A is 100 and the variance of factory B is 121.


Now, SD of factory A =


And, SD of factory B =


Therefore,


The CV of factory A =


The CV of factory B =


Here,the CV of factory B is greater than the CV of factory A.


Hence, factory B shows greater variability.


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