## If a smaller value appears to the right of a larger value, the smaller value is added to the larger.
So VI = 6 (V+I or 5 + 1), VII = 7 (V+I+I or 5 + 1 + 1), XI = 11 (X+I or 10 + 1)
## How to convert decimal numbers to Roman Numerals
First use your knowledge of place value to partition the number into thousands, hundreds, tens and units, so 1987 would be 1000 + 900 + 80 + 7
Next convert these values into Roman Numerals,
1000 is M, 900 is CM (1000-100), 80 is LXXX (50 + 10 + 10 + 10) and 7 is VII (5 + 1 + 1)
Put these letters together - MCMLXXXVII
## How to convert Roman Numerals to decimal numbers
FIrst we have to work out the groupings, remembering the rules, especially that if a smaller value is to the left of a larger value then the smaller value is subtracted from the larger.
Lets take MDCCCLVI, that is M DCCC L VI
M is 1000, DCCC is 800 (500 + 100 + 100 + 100), L is 50 and VI is 6 (5 + 1)
1000 + 800 + 50 + 6 = 1856 |