Which of these is a valid Roman numeral? Support your answer with reason in each case.
VCXVI

Answer

To determine if "VCXVI" is a valid Roman numeral, we need to analyze the components and rules of Roman numerals.

### Step-by-Step Solution:

1. **Identify the Roman Numerals**: The Roman numeral "VCXVI" consists of the following characters: V, C, X, V, and I.

2. **Understanding Roman Numeral Values**:
- V = 5
- C = 100
- X = 10
- I = 1

3. **Check the Order of Roman Numerals**:
- In Roman numerals, smaller values can be placed before larger values to indicate subtraction (e.g., IV = 4). However, a numeral cannot be placed before a larger numeral if it is not allowed to subtract.
- The numeral "V" (5) cannot be placed before "C" (100) because it does not follow the subtraction rule.

4. **Evaluate the Structure**:
- In "VCXVI", the "V" is followed by "C", which is not valid since "V" cannot be subtracted from "C". Therefore, "VC" is not a valid combination.

5. **Conclusion**: Since "VC" is not a valid combination in Roman numerals, "VCXVI" as a whole is not a valid Roman numeral.

### Final Answer:
"VCXVI" is not a valid Roman numeral because "V" cannot precede "C" to indicate subtraction.

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