Assume the selling price is Rs. 100, which makes the cost price 35% of Rs. 100, or Rs. 35. The profit formula is Profit equals Selling Price minus Cost Price, giving a profit of 100 - 35, which equals Rs. 65. To find the profit margin percentage, calculate Profit divided by Cost Price multiplied by 100, giving 65 / 35 * 100, which equals 185.71%.