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.