Christopher Ironside coins of the British Commonwealth had their reverse designed by Christopher Ironside. These coins were struck as (Board 1): Under the provision of the Manx Decimal Currency Act of 1970, a decimal series of coins for the Isle of Man were prepared and released on 20 October 1971 (½, 1, 2, 5, 10 and 50 new pence coins). The reverse of most of these coins was designed by Christopher Ironside. This set had the same composition and size as the corresponding British coins. These coins were struck as: 1971 first decimal set (issued from 1971 to 1974): As a country
Decimal decimal fractions were non-positional. However, counting rod fractions were positional. Qin Jiushao in his book Mathematical Treatise in Nine Sections (1247) denoted 0.96644 by J. Lennart Berggren notes that positional decimal fractions appear for the first time in a book by the Arab mathematician Abu'l-Hasan al-Uqlidisi written in the 10th century. The Jewish mathematician Immanuel Bonfils used decimal fractions around 1350, anticipating Simon Stevin, but did not develop any notation to represent them. The Persian mathematician Jamshīd al-Kāshī claimed to have discovered decimal fractions himself in the 15th century. Al Khwarizmi introduced fraction to Islamic countries in the early 9th