If the spot value ratio is equal to β, then the spot value is 225 million yuan and the futures value is the number of contracts *5700*300 (because the 300 yuan of the Shanghai and Shenzhen 300 Index contracts is every point), then the following calculation can be obtained:

(225000000 * 0.8)/(5700 * 300) =105.26 ~106 sheets.

Because the yield reaches 25%, I am afraid that the income will drop, so I have to do a sell hedging operation.

Thank you. I hope it helps you.