The average annual income (in Rs.) of certain agricultural workers is S and that of other workers is T. The number of agricultural workers is 11 times that of other workers. Then the average monthly income (in Rs.) of all the workers is-
Correct Answer: $$\frac{11S + T}{12}$$
Let the number of other workers be x
Then, number of agricultural workers = 11x
Total number of workers = 12x
∴ Average monthly income
$$\eqalign{ & = \frac{{S \times 11x + T \times x}}{{12x}} \cr & = \frac{{11S + T}}{{12}} \cr} $$
Then, number of agricultural workers = 11x
Total number of workers = 12x
∴ Average monthly income
$$\eqalign{ & = \frac{{S \times 11x + T \times x}}{{12x}} \cr & = \frac{{11S + T}}{{12}} \cr} $$