I sold 20 contracts that day and earned 30X 10X20=6000 yuan, that is, the margin increased to 2.6W yuan (the actual profit was 6000 yuan).

On the same day, he also held 20 soybean contracts with a floating profit of 20X 10X40=8000 yuan.

In other words, the actual profit is 600,000 yuan and the floating profit (book profit) is 800,000 yuan, excluding the commission.