Roman Numerals

Overview

Engineering reference data for Roman Numerals in miscellaneous.

Key Formulas

Unit Conversion

$y = x \cdot k$

Multiply by conversion factor.

Linear Interpolation

$y = y_1 + \frac{(x - x_1)(y_2 - y_1)}{x_2 - x_1}$

Estimate between two known points.

Percentage

$p = \frac{\text{part}}{\text{whole}} \times 100\%$

Part as fraction of whole.

Variables

Rules for Combining Roman Numerals

Roman numerals are formed by combining letters and applying these fundamental rules:

• Subtractive Rule: When a smaller value appears before a larger value, it is subtracted.

$$\text{Value} = \text{Larger} - \text{Smaller}$$

Example: IX = 10 - 1 = 9.

• Additive Rule: When a smaller value appears after a larger value, it is added.

$$\text{Value} = \text{Larger} + \text{Smaller}$$

Example: XI = 10 + 1 = 11.

• Repetition Rule: A numeral can be repeated up to three times to indicate addition.

$$\text{III} = 1 + 1 + 1 = 3$$

• Multiplicative Notation (Large Numbers): A horizontal line (vinculum) above a numeral multiplies its value by 1000.

$$\overline{V} = 5 \times 1000 = 5000$$ $$\overline{X} = 10 \times 1000 = 10{,}000$$

Common Roman Numeral Equivalents

This table summarizes frequently used Roman numerals and their integer values.

References

• Original Source