6th Grade Math Textbook, Progress

(Marvins-Underground-K-12) #1

Roman Numerals


The ancient Romans used the symbols given below
to represent numerals.

All other numerals are represented through
combinations of these seven different symbols.

Rules for Forming Roman Numerals

No symbol, except for M, is repeated more than
three times in a row.

When a symbol is followed by a symbol with an
equal or lesser value, addthe values of the symbols.
XX 10  10  20 CCC 100  100  100  300
DC 500  100  600 MD 1000  500  1500

When a symbol is followed by a symbol with a
greater value, subtractthe lesser value from the
greater value.
IX 10  1  9 XL 50  10  40
XC 100  10  90 CM 1000  100  900

Only subtract powers of ten (I, X, or C, but not V or L).
For the numeral 95, do NOT write VC (100 5).
Do write XCV (XC V or 90 5).

Sometimes you must add andsubtract.
MCMIV 1000 (1000 100) (5 1)  1904
CMLX(1000 100) (50 10)  960

Write each as a standard numeral.


  1. CL 2. XXXIX 3. MM 4. CDIX

  2. CMXC 6. LXVI 7. MCMXCV 8. MCLV


Write the Roman numeral for each.
0 9. 127 10. 1914 11. 4300 12. 6320

Symbol IV XL C D M
Value 1 5 10 50 100 500 1000

Think
Roman numerals I,
X, and C are
powers of ten.
I  100 X  101
C  102

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