In a bank, monthly salary of clerks and officers are in the ratio of $3 : 5$. Each clerk contributes 2% and each officer contributes 3 % of his salary to the Welfare Fund. If each officer's contribution is ₹ 210, what will be the clerk's salary?

### Concept & Percentage of Ratios When given a percentage of a proportional value, you can express the actual amount as a fraction of the ratio variable to solve for the unknown multiplier. ### Step-by-Step Solution 1. **Given:** Ratio of salaries for clerk to officer is $3 : 5$. 2. Let the clerk's salary be $3x$ and the officer's salary be $5x$. 3. Each officer contributes 3% of their salary. 4. Officer's contribution = $3\%$ of $5x = \frac{3}{100} \times 5x = 0.15x$. 5. We are given that the officer's contribution is ₹ 210. 6. Set up the equation: $0.15x = 210$. 7. Solve for $x$: $x = \frac{210}{0.15} = \frac{21000}{15} = 1400$. 8. The clerk's salary is $3x = 3 \times 1400 = 4200$. ### Exam Strategy & Shortcut Officer salary = $\frac{210}{0.03} = 7000$. The ratio of clerk to officer salary is $3 : 5$. Since 5 parts = 7000, 1 part = 1400. Clerk salary = 3 parts = $3 \times 1400 = 4200$. This completely avoids decimals containing variables. ### Common Pitfall Calculating the clerk's contribution amount instead of the clerk's total salary as requested by the question. ### Final Answer Therefore, the correct answer is **₹ 4200**.