Here is an ancient problem: There is a large jar filled with 8 jin (a unit of weight) of oil. Additionally, there are two empty bottles; one can hold 5 jin and the other can hold 3 jin. The task is to divide the oil into two equal portions of 4 jin each by pouring it back and forth between the jar and the two bottles. It is assumed here that there is no loss of oil during the pouring process. According to the history of mathematics, the first person to propose this problem was the 16th-century Italian mathematician Niccolò Fontana, who was also the first scholar to study the general solution of cubic equations in algebra. Regarding the aforementioned problem, his solution is as follows: