79 in Roman numerals
79 is written LXXIX. In chunks: L (50) + X (10) + X (10) + IX (9) = 79.
The answer
LXXIX
79 in Roman numerals is LXXIX.
How LXXIX is built
To write it, split 79 into 70 + 9. 70 is LXX, 9 is IX, so 79 is LXX then IX: LXXIX.
To read it, LXXIX has 4 chunks, and IX is a take-away pair, worked out first and then added.
| Chunk | Worth | Why |
|---|---|---|
| L | 50 | Add |
| X | 10 | Add |
| X | 10 | Add |
| IX | 9 | I before X: take away |
The mistake to watch for
Writing 79 as LXXVIIII
Wrong: LXXVIIII
LXXVIIII writes I four times in a row. Never more than three: 9 is IX, one before ten, which makes 79 LXXIX.
Check it with the converter
Type LXXVIIII to see why LXXVIIII is not 79. The rule numbers it gives are the three rules on the Roman numerals page.
Converter set to LXXIX (79).
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Questions parents ask
What is 79 in Roman numerals?
79 is LXXIX.
What comes before and after LXXIX?
78 is LXXVIII and 80 is LXXX.
Does LXXIX use subtraction?
Yes, once: I comes before the bigger X, so IX is 9. The other letters are added.
What is the biggest letter in LXXIX?
L, which is 50. LXXIX has 5 letters.
Careful reading is an 11+ skill
Reading all 5 letters of LXXIX in order is the careful checking 11+ papers reward. The free diagnostic covers all four subjects, with no card needed.