Subroto sold an article for ₹ 528 after allowing a discount of 12% on its marked price. What was the marked price of the article?

### Concept & Formula The Selling Price (SP) is calculated by subtracting the discount from the Marked Price (MP). The discount is always calculated as a percentage of the Marked Price. $$SP = MP \times \left(1 - \frac{\text{Discount}\%}{100}\right)$$ ### Step-by-Step Solution 1. Let the Marked Price (MP) of the article be $x$. 2. Discount allowed = $12\%$. 3. Selling Price (SP) after the discount is ₹ 528. 4. Set up the equation: $$x \times (100\% - 12\%) = 528$$ $$x \times 88\% = 528$$ $$0.88x = 528$$ 5. Solve for $x$: $$x = \frac{528}{0.88}$$ Multiply the numerator and the denominator by 100 to remove the decimal: $$x = \frac{52800}{88}$$ $$x = 600$$ ### Exam Strategy & Shortcut If $12\%$ is the discount, the customer pays $88\%$ of the marked price. $88\% \equiv 528$ Divide by 88 to find $1\%$: $1\% \equiv 6$ Multiply by 100 to find $100\%$ (the Marked Price): $100\% \equiv 600$. ### Common Pitfall A common pitfall is calculating $12\%$ of the selling price (528) and adding it back, which mathematically yields the wrong base value. Discount is strictly applied on the Marked Price. ### Final Answer Therefore, the correct answer is **₹ 600**.