1. **State the problem:** An item costs 500. The original selling price is 650. Later, 200 was added to the original selling price, and it was later tagged to sell at 630. 2. **Formulas and rules:** - Mark-on = Original Selling Price - Cost - New Selling Price = Original Selling Price + Additional Mark-on - Markdown = New Selling Price - Tagged Selling Price 3. **Calculate the mark-on:** $$\text{Mark-on} = 650 - 500 = 150$$ 4. **Calculate the new selling price:** $$\text{New Selling Price} = 650 + 200 = 850$$ 5. **Calculate the markdown:** $$\text{Markdown} = 850 - 630 = 220$$ **Final answers:** - Mark-on = 150 - New Selling Price = 850 - Markdown = 220