Roman numerals

[REWD]

How were mathematical problems e.g. multiplication and division carried out.

[grannog]

Try the information at this address.

http://mathforum.org/library/drmath/view/57564.html

[Peter Pedant]

I read somewhere that they also had look up tables - on the URL given, Dr Math doesnt mention this.

so that for 25 x 25 which I think is 625

XXV times XXV a table would give you x times xxv, so you add that twice to whatever the look up says v times xxv is.

This effectively converts multiplication to addition.

Roman number system was bi-quinary

five time I is V,

twice V is X

five times X is L

twice L is C

five times C is D and twice D is M

but it is not really place ordered. so IX is one minus ten, where as in our system 565 can never mean takes 5 from 6 under any circs.

so multiplying IX by MCM, perhaps they really did look up X times MCM and take away MCM......

Anyway I now see why algebra (arabic derivation) awaited the more 'obvious' arabic number system......

[REWD]

Thanks to all, Most helpful

[Octavius]

Roman numerals and calculations were complicated by the lack of a symbol for 'zero', which only appeared from about 1,000 AD.

I had far too much to drink last night to give a full explanation of roman mathematics, maybe this will help, while I pop off for an Alker seltzer: http://www.legionxxiv.org/numerals/