House rent spending = 10% of salary, Conveyance spending = 50% of remainder, Remaining amount = ₹20,556

Use the fraction multiplier method: Salary = $20556 \times \frac{100}{90} \times \frac{100}{50}$. This simplifies to $20556 \times \frac{10}{9} \times 2 = 2284 \times 20 = 45680$.

Students often add the percentages (10% + 50% = 60%) and assume 40% remains, which is incorrect because the second percentage is calculated on the remaining balance, not the original salary.

This logic is identical to calculating successive discounts in profit and loss or depreciation in compound interest problems.