[[Imageไฟล์:Ybc7289Ybc7289-bw.jpg|thumb|250px250px|right|Babylonian clay tablet YBC 7289 (c. 1800–16001800–1600 BC) with annotations. The approximation of the [[square root of 2]] is four [[sexagesimal]] figures, which is about six [[decimal]] figures. 1 + 24/60 + 51/60<sup>2</sup> + 10/60<sup>3</sup> = 1.41421296...<ref>[http://it.stlawu.edu/%7Edmelvill7Edmelvill/mesomath/tablets/YBC7289YBC7289.html Photograph, illustration, and description of the ''root(2)'' tablet from the Yale Babylonian Collection]</ref>]]
