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E:\Working\Focus_Learning\Math_Genius_4_(25-10-2023)\Open_Files\Chap-01
\\December 6, 2023 1:30 PM Bharat Arora P-6 Reader _________________________ Date: ___________________74

rule 3: The smaller numeral written to the left of the larger numeral is always subtracted
from the larger numeral.

examples: (a) IV = 5 – 1 = 4 (b) XL = 50 – 10 = 40

(c) XC = 100 – 10 = 90

Note: Roman numeral ‘I’ can only be subtracted from V and X. X can be
subtracted from L and C only. C can be subtracted from D and M only. V, L

and D are never subtracted.

rule 4: When the smaller numeral is placed between two larger numerals, then it is
always subtracted from the larger numeral immediately following it.

examples: (a) XIV = 10 + (5 – 1) = 14

(b) XIX = 10 + (10 – 1) = 19

(c) XLIX = (50 – 10) + (10 – 1) = 40 + 9 = 49
example 1: Write the following Hindu-Arabic numerals in Roman numerals.

(a) 48 (b) 97 (c) 175 (d) 389
Solution:
Remember
(a) 48 = 40 + 8 = XL + VIII = XLVIII Learn the mnemonic to remember
the sequence of Roman numeral:
(b) 97 = 90 + 7 = XC + VII = XCVII I Value Xylophones Like

(c) 175 = 100 + 70 + 5 = C + LXX + V = CLXXV Cows Do Milk

(d) 389 = 300 + 80 + 9 = CCC + LXXX + IX = CCCLXXXIX

example 2: Write the following Roman numarals in Hindu-Arabic numerals.
(a) XLV (b) LXV (c) CXXIX (d) CCCXLV

Solution:

(a) XLV = (50 – 10) + 5 = 40 + 5 = 45 Life Skills
List the five things or objects, where
(b) LXV = 50 + 10 + 5 = 65 you often see the use of Roman

(c) CXXIX = 100 + 20 + 9 = 129 numerals around you.
(d) CCCXLV = 100 + 100 + 100 + (50 – 10) + 5 = 300 + 40 + 5 = 345

Think and Answer
Find the following and fill in the blanks using the Roman numerals.
1. Your father’s age = ___________________
2. Your mother’s age = ___________________
3. Date of birth of your best friend = ___________________
4. Date on which India became independent = ___________________

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