Given: A trader marked up his articles 25% more than the cost price. He offered a discount of 10% Formula used: Selling price = Mark price × (100 – discount)% Profit% = (selling price - cost price)/cost price × 100 Calculation: Let the cost price be 100. Mark price = 100 × 125% = 125 Selling price = 125 × 90% = 450/4 = 112.5 Profit% = (12.5/100) × 100 = 12.5% ∴ Trader’s profit percentage is 12.5%.