Halfpenny (British decimal coin) Halfpenny (British decimal coin) The British decimal halfpenny (p) coin was introduced in February 1971, at the time of decimalisation, and was worth one two-hundredth of a pound sterling. It was ignored in banking transactions, which were carried out in units of 1p. The decimal halfpenny had the same value as 1.2 pre-decimal pence, and was introduced to enable the prices of some low-value items to be more accurately translated to the new decimal currency. The possibility of setting prices including an odd half penny also made it more practical to retain the pre-decimal sixpence in circulation (with a value
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