Coins of the New Zealand dollar of one pound to two dollars (10 shillings to a dollar). On the same day, new decimal coins were introduced to replace the existing pound coins. The first coins of the New Zealand dollar were 1c, 2c, 5c, 10c, 20c, and 50c. The 1c, 2c, and 50c coins were new sizes, with the 1c and 2c minted in bronze, and 50c in cupronickel. The new 5c, 10c, and 20c were the same size, weight, and value as the former sixpence, shilling, and florin coins. Indeed, until 1970, the 10 cents coin bore the additional legend "One Shilling". The obverse designs
Cocker's Decimal Arithmetick Cocker's Decimal Arithmetick Cocker's Decimal Arithmetick is a grammar school mathematics textbook written by Edward Cocker (1631–1676) and published posthumously by John Hawkins in 1684. "Decimal Arithmetick" along with companion volume, "Cocker's Arithmetick" published in 1677, were used in schools in the United Kingdom for more than 150 years. The concept of decimal fractions and the advantages of using them in calculations were well known, but a wide variety of different notations were in use. After surveying various notations, "Decimal Arithmetick" recommends the decimal point notation introduced by John Napier: "Decimal Arithmetick" gives instructions for calculations involving decimals, methods of