UPSC Prelims 2008 Q106: Science & Technology – Number systems / Roman numerals
Which one of the following is the correct sequence in respect of the Roman numerals - C, D,
L and M?
- (a) C > D > L > M
- (b) M > L > D > C
- (c) M > D > C > L
- (d) L > C > D > M
Answer: (c) M > D > C > L
Explanation
Correct sequence of Roman numerals C, D, L, and M
Each Roman numeral represents a specific numeric value, which we need to arrange in decreasing order.
| Numeral | Value |
|---|---|
| C | 100 |
| D | 500 |
| L | 50 |
| M | 1000 |
Arranging in decreasing order:
| Rank | Numeral | Value |
|---|---|---|
| 1st | M | 1000 |
| 2nd | D | 500 |
| 3rd | C | 100 |
| 4th | L | 50 |
Answer: (c) M > D > C > L.
Why each option is right or wrong
- (a) Incorrect. 'C > D > L > M' places the smallest-to-largest values in the wrong order entirely.
- (b) Incorrect. 'M > L > D > C' incorrectly places L (50) ahead of D (500) and C (100).
- (c) CORRECT. M (1000) > D (500) > C (100) > L (50) is the correct decreasing order of values.
- (d) Incorrect. 'L > C > D > M' reverses the entire correct order.
Key point
In decreasing order of value: M (1000) > D (500) > C (100) > L (50).
Remember
Decreasing order of C, D, L, M: M > D > C > L.
Common mistakes
- Misremembering the specific numeric values of these Roman numerals (especially confusing L and C, or D and M).
- Reversing the entire sequence, listing smallest to largest instead of largest to smallest.
- Not having basic Roman numeral values memorised (I=1, V=5, X=10, L=50, C=100, D=500, M=1000).
Exam tip
Roman numeral values: M=1000, D=500, C=100, L=50. Memorise this basic numeral-value table.
Sources
- NCERT Class VI Mathematics — Knowing Our Numbers (Roman numerals)
- Encyclopaedia Britannica — Roman numeral