There are two types of employees in Sun Metals, general graduates and engineers. 40% of the employees in Sun Metals are general graduates, and 75% of the engineers earn more than Rs. 5 lakh/year. If 50% of the organisation’s employees earn more than Rs. 5 lakh/year, what proportion of the general graduates employed by the organisation earn Rs. 5 lakh or less?

Let total employees in Sun Metals = $$100x$$

Number of employees who are general graduates = $$\frac{40}{100} \times 100x = 40x$$

=> Number of employees who are engineers = $$100x - 40x = 60x$$

Now, number of engineers who earn more than Rs. 5 lakh/year = $$\frac{75}{100} \times 60x = 45x$$

Number of employees (both general graduates and engineers) who earn more than Rs. 5 lakhs/year = $$\frac{50}{100} \times 100x = 50x$$

=> Number of general graduates who earn more than Rs. 5 lakhs/year = $$50x - 45x = 5x$$

Thus, number of general graduates who earn less than Rs. 5 lakhs/year = $$40x - 5x = 35x$$

$$\therefore$$ Proportion of the general graduates employed by the organisation earn Rs. 5 lakh or less

= $$\frac{35 x}{40 x} = \frac{7}{8}$$