40% of the employees in a factory are workers.

Solution(By Apex Team)

Let X be the number of employees. We are given that 40% of the employees are workers. Now, 40% of X is $\frac{40}{100} \times X=0.4 X$ Hence, the number of workers is $\frac{2 \mathrm{X}}{5}$ All the remaining employees are executives, so the number of executives equals, (The number of Employees) − (The number of Workers) $\begin{array}{l}=X-\Large\frac{2X}{5}\\ =\Large\frac{3X}{5}\end{array}$ The annual income of each worker is Rs. 390. Hence, the total annual income of all workers together is $=\frac{2 \mathrm{X}}{5} \times 390=156 \mathrm{X}$ Also, the annual income of each executive is Rs.420. Hence, the total income {of all the executives together is, $=\frac{3 \mathrm{X}}{5} \times 420=252 \mathrm{X}$ Hence, the total income of the employees is, = 156X + 252X = 408X The average income of all the employees together equals