''Cocker's Decimal Arithmetick'' is a

grammar school A grammar school is one of several different types of school in the history of education in the United Kingdom and other English-speaking countries, originally a school teaching Latin, but more recently an academically oriented secondary school, ...

mathematics textbook written by

Edward Cocker Edward Cocker (163122 August 1676) was an English engraver, who also taught writing and arithmetic. Cocker was the reputed author of the famous ''Arithmetick'', the popularity of which has added a phrase ("according to Cocker") to the list of ...

(1631–1676) and published posthumously by John Hawkins in 1684. ''Decimal Arithmetick'' along with companion volume, ''

Cocker's Arithmetick ''Cocker's Arithmetick'', also known by its full title "Cocker's Arithmetick: Being a Plain and Familiar Method Suitable to the Meanest Capacity for the Full Understanding of That Incomparable Art, As It Is Now Taught by the Ablest School-Masters ...

'' 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 A decimal separator is a symbol used to separate the integer part from the fractional part of a number written in decimal form (e.g., "." in 12.45). Different countries officially designate different symbols for use as the separator. The ch ...

notation introduced by

John Napier John Napier of Merchiston (; 1 February 1550 – 4 April 1617), nicknamed Marvellous Merchiston, was a Scottish landowner known as a mathematician, physicist, and astronomer. He was the 8th Laird of Merchiston. His Latinized name was Ioa ...

: :''A decimal fraction being written ... by having a point or prick prefixed before it ... being written according to the first direction, I conceive they may be most fit for calculation.'' ''Decimal Arithmetick'' gives instructions for calculations involving decimals, methods of extracting roots, and an overview of the concept of logarithms. There are many worked examples, some of which involve solid geometry or the calculation of interest.

References

{{reflist 1678 books Mathematics textbooks Mathematics education in the United Kingdom