The document consists of a mathematical method from the Warring States Period (475-221 BC), according to Li Xueqin, head of the Research and Conservation Center for Excavated Texts of Tsinghua University here.
The unearthed document provides a method for the multiplication of any two whole numbers under 100 and certain fractions, said Li, a well-known historian.
The document is the earliest of its kind discovered so far and has filled in a historical blank for math documents prior to the Qin Dynasty (221 BC - 206 BC), the official Xinhua news agency quoted Guo Shuchun, director of the Chinese Society of the History of Mathematics as saying.
In July 2008, Tsinghua University had acquired a rare collection of 2,500 slip bamboo items belonging to the late Warring States period, which had been smuggled out of China.