45 in Roman numerals
45 is written XLV. In chunks: XL (40) + V (5) = 45.
The answer
XLV
45 in Roman numerals is XLV.
How XLV is built
To write it, split 45 into 40 + 5. 40 is XL, 5 is V, so 45 is XL then V: XLV.
To read it, XLV has 2 chunks, and XL is a take-away pair, worked out first and then added.
| Chunk | Worth | Why |
|---|---|---|
| XL | 40 | X before L: take away |
| V | 5 | Add |
The mistake to watch for
Writing 45 as VL
Wrong: VL
VL looks like "50 take away 5", but only four pairs ever subtract up to 100: IV, IX, XL and XC. Split 45 into 40 and 5 instead: XL and V make XLV.
Check it with the converter
Type VL to see why VL is not 45. The rule numbers it gives are the three rules on the Roman numerals page.
Converter set to XLV (45).
Keep going
Questions parents ask
What is 45 in Roman numerals?
45 is XLV.
What comes before and after XLV?
44 is XLIV and 46 is XLVI.
Does XLV 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 XLV?
L, which is 50. XLV has 3 letters.
Careful reading is an 11+ skill
Reading all 3 letters of XLV in order is the careful checking 11+ papers reward. The free diagnostic covers all four subjects, with no card needed.