The cost price is 200 yuan. If I sell it for 500 yuan, I only charge 30% of the profit. What is the fastest and most convenient way?

The cost price is 200 yuan. If I sell it for 500 yuan, I only charge 30% of the profit. What is the fastest and most convenient way?

Your profit receivable: (500-200) * 0.3 = 90
If the selling price and cost are fixed, your profit of 18 yuan per 100 yuan is 18% of the total amount