Roman Numbers details

ROMAN NUMBERS

INTERPRETING SYMBOLS

Convert Roman Numerals

 This list will teach students what each Roman numeral stands for and provide tips on remembering why each symbol represents what it does.

·        I -stands for “1” .

·        V -stands for “5” .

·        X – stands for “10” .

·        L -stands for “50”.

·        C – stands for “100” .

·        D- stands for “500”.

·        M- stands for “1000”.

RULES

1.    Only one smaller digit can be on the left side of the larger digit. For example, the number 7 would be written as “VII” rather than “IIIX”.

2.    If the digit to the left represents a smaller amount than the digit to the right, it is to be subtracted from the digit on the right. For example “IV” means 4.

3.    If the digit to the right is smaller than the digit on the left, the numbers shall be added together. For example “VI” means 6.

4.    The smaller digit on the left can be no less than 10% of the digit on the right. For example, “IM” is not a “legal” form of 999. It would instead be written as “CMXCIX”.

5.    The least amount of digits must be used without breaking any of the other rules. For example, thought XXXX can mean “50”, you would instead use the “L”.

HOW TO READ ROMAN NUMERALS REVIEW

MDCXVI

When you look at this number, the first thing to look for is to see if there are any digits representing smaller digits on the left side of the larger digits.

The answer to this question will tell you what math function to perform. In this case, the digits descend from highest to lowest where M=1000, D=500, C=100, X=10, V=5 and I=1. This tells you that you will add the numbers together, which is something you will do as the last step in deciphering every Roman numeral. The number is 1616 by the formula of 1000+500+100+10+5+1.

Lets practice using the following numbers.

·        CVII (107)

·        MDX (1510)

·        MC (1100)

Sometimes you will have to subtract before you can add when converting Roman numerals to standard numbers.

Use the number below as an example.

MCMXCIV

There is a C before the M, an X before the C and a I before the V. Before taking the last step in converting the Roman numerals by adding them, you must first subtract the smaller numbers on the left from the larger ones on the right. The formula for figuring out this Roman numeral would look like this;

 1000 + (1000-100) + (100- 10) + (5-1)

because the way the Roman numeral is written is actually the formula listed after this sentence. M + (M-C) + (C-X) + (V-I)

We simply translated it! The answer to the formula is 1994.

Convert the Roman numerals below.

·        MM (2000)

·        MCMVI (1906)

·        XXIII (23)

·        LVI (56)

·        DIII (503)

·        MCDIV (1404)