Grade 5, Maths Olympiad (CBSE) - Roman numbers 

Grade 5  |   Maths  |   Roman numbers, Numerals and Numbers, Olympiad, CBSE, ICSE, Maths Olympiad, Science Olympiad, English Olympiad

Roman Numbers

Number system which we use generally is called the arabic number system. It consists of digits like 1, 2, 3, 4, 5....9 etc.

Roman numbers is another number system. Numbers are represented as I, II, X etc.

Rules:

1. I means 1, II means 2 and III means 3.
2. V is 5, X is 10.
3. L is 50, C is 100, D is 500 and M is 1000.
4. One symbol cannot be used continuously 3 times in a row.
5. Only I, X, C and M can be repeated. V, L and D cannot be repeated.
6. If we place a symbol of smaller value before another symbol of greater value then we have to subtract the smaller number from bigger number.
   E.g.
   IV means 5 - 1=4
7. Only one number can be subtracted from another number. E.g. IIX is incorrect.
8. If we place a symbol of smaller value after another symbol of greater value then 2 numbers are added.
   E.g.
   VII means 5 + 2=7
9. Repeated symbols are added. E.g. XX=10 + 10=20
10. Bigger numbers can be represented by adding a bar at the top of the symbol which means the value of the number is multiplied by 1000.
    E.g. 
    _
    L=50 X 1000=50000