Let's solve each problem step by step.
We are adding Roman numerals and converting them to Arabic numbers (standard numbers), then converting the sum back into Roman numerals.
Roman Numeral Basics:
- I = 1
- V = 5
- X = 10
- L = 50
Rules for subtraction:
- IV = 4 (5 - 1)
- IX = 9 (10 - 1)
- XL = 40 (50 - 10)
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Now, let’s go through each row:
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1) XV + VI
- XV = 10 + 5 = 15
- VI = 5 + 1 = 6
- 15 + 6 = 21
- 21 in Roman numerals = XXI
✔ (Given as example)
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2) XII + XI
- XII = 10 + 1 + 1 = 12
- XI = 10 + 1 = 11
- 12 + 11 = 23
- 23 = XXIII
✔ Answer: 23 = XXIII
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3) XV + XV
- XV = 15
- 15 + 15 = 30
- 30 = XXX
✔ Answer: 30 = XXX
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4) XI + IX
- XI = 11
- IX = 9
- 11 + 9 = 20
- 20 = XX
✔ Answer: 20 = XX
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5) XXV + XI
- XXV = 20 + 5 = 25
- XI = 11
- 25 + 11 = 36
- 36 = XXXVI
✔ Answer: 36 = XXXVI
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6) XX + XX
- XX = 20
- 20 + 20 = 40
- 40 = XL
✔ Answer: 40 = XL
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7) XXV + VIII
- XXV = 25
- VIII = 5 + 1 + 1 + 1 = 8
- 25 + 8 = 33
- 33 = XXXIII
✔ Answer: 33 = XXXIII
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8) XIV + XI
- XIV = 10 + (5 - 1) = 14
- XI = 11
- 14 + 11 = 25
- 25 = XXV
✔ Answer: 25 = XXV
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9) XIX + XII
- XIX = 10 + (10 - 1) = 19
- XII = 12
- 19 + 12 = 31
- 31 = XXXI
✔ Answer: 31 = XXXI
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10) XXX + XII
- XXX = 30
- XII = 12
- 30 + 12 = 42
- 42 = XLII
✔ Answer: 42 = XLII
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11) XXXI + XV
- XXXI = 30 + 1 = 31
- XV = 15
- 31 + 15 = 46
- 46 = XLVI
✔ Answer: 46 = XLVI
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12) XXV + IX
- XXV = 25
- IX = 9
- 25 + 9 = 34
- 34 = XXXIV
✔ Answer: 34 = XXXIV
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13) XIV + IX
- XIV = 14
- IX = 9
- 14 + 9 = 23
- 23 = XXIII
✔ Answer: 23 = XXIII
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14) XX + XXIII
- XX = 20
- XXIII = 23
- 20 + 23 = 43
- 43 = XLIII
✔ Answer: 43 = XLIII
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15) XXII + XVI
- XXII = 22
- XVI = 16
- 22 + 16 = 38
- 38 = XXXVIII
✔ Answer: 38 = XXXVIII
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16) XXXIV + XV
- XXXIV = 30 + 4 = 34
- XV = 15
- 34 + 15 = 49
- 49 = XLIX (because 50 - 1 = 49 → XLIX)
✔ Answer: 49 = XLIX
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✔ Final Answers:
| # | Addition | Number | Roman Numeral |
|---|---------|--------|----------------|
| 1) | XV + VI | 21 | XXI |
| 2) | XII + XI | 23 | XXIII |
| 3) | XV + XV | 30 | XXX |
| 4) | XI + IX | 20 | XX |
| 5) | XXV + XI | 36 | XXXVI |
| 6) | XX + XX | 40 | XL |
| 7) | XXV + VIII | 33 | XXXIII |
| 8) | XIV + XI | 25 | XXV |
| 9) | XIX + XII | 31 | XXXI |
| 10) | XXX + XII | 42 | XLII |
| 11) | XXXI + XV | 46 | XLVI |
| 12) | XXV + IX | 34 | XXXIV |
| 13) | XIV + IX | 23 | XXIII |
| 14) | XX + XXIII | 43 | XLIII |
| 15) | XXII + XVI | 38 | XXXVIII |
| 16) | XXXIV + XV | 49 | XLIX |
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Parent Tip: Review the logic above to help your child master the concept of roman numeral worksheet high school.
