42 in Roman numerals
42 is written XLII. In chunks: XL (40) + I (1) + I (1) = 42.
The answer
XLII
42 in Roman numerals is XLII.
How XLII is built
To write it, split 42 into 40 + 2. 40 is XL, 2 is II, so 42 is XL then II: XLII.
To read it, XLII has 3 chunks, and XL is a take-away pair, worked out first and then added.
| Chunk | Worth | Why |
|---|---|---|
| XL | 40 | X before L: take away |
| I | 1 | Add |
| I | 1 | Add |
The mistake to watch for
Writing 42 as XXXXII
Wrong: XXXXII
XXXXII writes X four times in a row. Never more than three: 40 is XL, ten before fifty, which makes 42 XLII.
Check it with the converter
Type XXXXII to see why XXXXII is not 42. The rule numbers it gives are the three rules on the Roman numerals page.
Converter set to XLII (42).
Keep going
Questions parents ask
What is 42 in Roman numerals?
42 is XLII.
What comes before and after XLII?
41 is XLI and 43 is XLIII.
Does XLII use subtraction?
Yes, once: X comes before the bigger L, so XL is 40. The other letters are added.
What is the biggest letter in XLII?
L, which is 50. XLII has 4 letters.
Careful reading is an 11+ skill
Reading all 4 letters of XLII in order is the careful checking 11+ papers reward. The free diagnostic covers all four subjects, with no card needed.