The second book collects some famous arithmetic problems, such as the problem of "chickens and rabbits in the same cage" with known head and tail numbers, and there is also a congruence problem, that is, "I don't know the number of things today, three or three numbers win two, five or five numbers win two, seven or seven numbers win two, and ask the geometry of things."
Extended data:
Sun Tzu's Art of War discusses in detail the units of measurement and the system and method of calculation. Metrology includes length (degree), mass (quantity) and volume/volume (balance). The basic unit of length is a silk (one drop in diameter) spit out by a silkworm, with a decimal number on it. The basic unit of mass is the mass of a millet, and the basic unit of volume and volume is the volume of a millet.
After that, the empirical ratio of grain to refined grain and rice was recorded: the volume of rice boiled by millet was three fifths, and that of rice boiled by millet was five fifths.
Nantong Municipal Government-Sun Tzu's Calculation