Konverter tall til og fra romertall
Numbers above 3,999 use vinculum notation: a line above a numeral multiplies its value by 1,000.
So ICCCXXV = 1 000 325.
Did you know?
Fibonacci's Sales Pitch
Fibonacci didn't invent Hindu-Arabic numerals — they originated in India around 500 AD. But his 1202 book Liber Abaci was essentially a 600-page argument that these new numbers were better for business. He showed European merchants how place value and zero could transform trade and banking. He was right. By 1500, the debate was over.
Read more →The Subtraction Rule: Elegant Shorthand
The subtraction rule is what makes Roman numerals clever rather than just tedious. Instead of writing IIII for 4, you write IV: "one before five." Instead of DCCCC for 900, you write CM: "one hundred before one thousand." Only six subtractive pairs exist (IV, IX, XL, XC, CD, CM), and once you know them, you can read any Roman numeral instantly.
Read more →Hvor kommer romertall fra?
Man tror romertall stammer fra håndsignaler og tellemerker. Streken I representerer en finger, V representerer åpningen mellom tommel og fingre for fem, og X representerer kryssede hender for ti. Bokstavene L, C, D og M kommer fra modifikasjoner av greske bokstaver som chi, theta og phi for å representere 50, 100, 500 og 1 000. Over tid ble disse merkene til de latinske bokstavene folk kjenner igjen i dag. Det finnes ingen 0 i det romerske alfabetet, ettersom konseptet for tallet 0 ikke ble fullt utviklet før India oppfant det rundt 600 e.Kr. / 10600 HE.