The document discusses the Roman numeral system. It lists the seven basic symbols used - I, V, X, L, C, D, and M, along with their values. It then outlines four rules for writing numbers using Roman numerals: 1) repetition of I and X indicates addition, 2) smaller numbers to the right of larger are added, 3) I to the left of V or X is subtracted, and 4) numbers between 10-40 are written as groups of tens and ones. Several examples are provided to demonstrate the rules. The document concludes by providing practice problems to convert between Hindu-Arabic and Roman numerals.

1. ROMAN NUMERALS
In India people speak different languages and so use different regional
numerals for writing numbers .But Romans used other symbols for writing
numbers. They used only seven basic symbols listed below.
I V X L C D M
1 5 10 50 100 500 1000
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2. RULE 1 :
Repetition of I and X means addition.
e.g. II = 1+1 = 2 ; XXX = 10+10+10 = 30.
NOTES :
 ‘I’ and ‘X’ can be repeated at the most three times.
 ‘V’ is never repeated.
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3. RULE 2 :
If a smaller number is written to the right of a larger one,
is added to the larger.
e.g. VI = 5+1 = 6 ; XV = 10+5 = 15.
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4. RULE 3 :
If I is written to the left of V or X , it is subtracted.
e.g. IV = 5 – 1 = 4 ; IX = 10 – 1 =9.
NOTES :
 V is never written to the left of X.
 I is written only once to the left of V and X.
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5. RULE 4 :
For numbers between 10 and 40, we first write the number in
groups of tens and ones and then write the Roman numeral.
e.g. 22 = 10 + 10 + 2 = XXII.
39 = 10 + 10 + 10 + 9 = XXXIX.
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6. Example :
a) XXV = 10 + 10 + 5 = 25.
b) XXXI = 10 + 10 + 10 + 1 = 31.
c) CI = 100 + 1 = 101.
d) 24 = 10 + 10 + 4 = XXIV.
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7. 11/18/2019
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Q 1: What’s the time ?
Ans: It’s 10.05
 TRY THIS OUT.
Q 2: What’s the time ?
Ans: ……………….

8. CONVERT THE FOLLOWING HINDU-ARABIC
NUMERALS INTO ROMAN AND VICE-VERSA
a) 27 = ?
b) 51 = ?
c) 87 = ?
d) XXV = ?
e) XII = ?
f) XL = ?
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9. THANK YOU
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