Multicultural Mathematical Activities - Multiplication Around the World
This activity looks at five different methods for multiplication that have been used at various times and in various places:
The Grid Method was known to the Ancient Greeks, and is included in Euclid’s Elements. It has enjoyed something of a revival recently, thanks to the National Numeracy Strategy!
The Russian Peasant Method has some similarities with the Egyptian method. The method has a very pleasing ‘Wow!’ factor, as it seems to rely on sloppy working and the correct answer seems to appear by magic!
Gelosia is a method imported (like so many other mathematical ideas) into Europe from India in the middle ages. The present name for the method derives from a type of Venetian window frame!
Napier’s Bones are a technological development of the Gelosia method, developed by John Napier (1550 – 1617) of Scotland, who also developed a system of logarithms and the notation for the decimal point. The products needed in the Gelosia method were engraved on strips of wood or bone, and the answer could be found by arranging the strips appropriately. Sets of Napier’s Bones were usually fixed to each face of a square-sectioned rod, allowing several repeated strips in a set.
Each sheet consists of a summary of the method, intended for teachers, and based on a common example. There are brief notes on the working of the method, and suggestions for extensions where appropriate. A poster (file size 84KB) showing the various methods is also provided; this is supplied in A4 format, and can be enlarged for classroom display.