What does XL mean in Roman numerals?

XL means 40. When a smaller letter stands just before a bigger one, you take it away instead of adding it, so XL is 50 − 10. The standard form uses this in six pairs only: IV is 4, IX is 9, XL is 40, XC is 90, CD is 400 and CM is 900. Every other letter is simply added.

How do you write numbers in Roman numerals?

Write a number in Roman numerals one place value at a time, from the biggest down. Split 386 into 300, 80 and 6. Then write each part: 300 is CCC, 80 is LXXX and 6 is VI. Join them in that order to get CCCLXXXVI. A 4 or a 9 in any place needs a subtracting pair, as in 94, which is XCIV.

What is the easiest way to learn Roman numerals?

The easiest way to learn Roman numerals is to master the seven letters first and the rules second. C is the first letter of the Latin word centum, a hundred, and M of mille, a thousand. The letters for five are halves: V is half of X, L is half of C, and D is half of M. After that, reading is mostly adding.

Why does my child write IIII instead of IV?

Many children write IIII because they have seen it on clock faces, where four is often shown that way, and four ones feel logical. The standard form is IV, and only IV counts as a correct answer in the game. One rule settles it: the same letter never appears more than three times in a row, so 4 must be IV.

Is this Roman numeral game free for a whole class?

Yes, all six levels are free for a whole class, right in a browser, with nothing to download and no accounts. For Roman numeral practice at the board, write 1 to 30 in three rows of ten. Pupils spot that the endings I to IX return after X in the second row and after XX in the third. Then each pupil takes a tablet and plays. The schools plan adds per-student pricing and a teacher dashboard of who is improving.

Math practice · reimagined

Roman Numerals Game

This Roman numeral game has you read numerals up to MCMXCIX, or 1999, then answer in letters on a keypad of I, V, X, L, C, D and M. Decode faster than your rival, and your fighter lands the first blow.

Ages 4–99+ · no download · plays in your browser · 23 languages

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What are Roman numerals?

Roman numerals are a way of writing numbers with seven letters: I is 1, V is 5, X is 10, L is 50, C is 100, D is 500 and M is 1000. There is no zero. Letters side by side are added, so VI is 6 and XX is 20. You still see them in book chapters.

Every level of Roman numerals

Example: which number is LXIV?

The screen shows LXIV and asks you to pick its value from 64, 72 and 74.
Start with the first two letters: L is 50 and X is 10, which makes 60.
The last two letters, IV, stand for one less than five, so they add 4.
Since 60 + 4 = 64, you tap 64.

Learn it step by step

Romans wrote numbers with letters. Each letter is worth a fixed amount, and you mostly just add them up left to right.

XII is X(10) + I(1) + I(1) = 12. The one twist: when a smaller letter sits BEFORE a bigger one, you subtract it — IV is 5 − 1 = 4, and IX is 10 − 1 = 9.

Read the letters, add them up, and type the everyday number.

Tips and common mistakes

Letters repeat a one, five, ten pattern: I, V, X are 1, 5, 10; X, L, C are 10, 50, 100; C, D, M are 100, 500, 1000.
A common mistake is writing 99 as IC. Only I, X and C are ever subtracted, and only from the next two letters up, so 99 is XCIX.
Open any book at a random page and write its page number in Roman numerals. Your child reads it back to check, then you swap roles on the next page.

How to play

Reading rounds show a numeral such as XXVII, and you type 27 on the keypad or tap it among three or four numbers. Writing rounds flip it: a number like 49, or a sum like XIV + IX, and you spell the answer with seven letter keys. Get there first and Mushroom strikes, with more force the faster you were.

— Quick answers —

Roman numerals: the short FAQ

What does XL mean in Roman numerals?: XL means 40. When a smaller letter stands just before a bigger one, you take it away instead of adding it, so XL is 50 − 10. The standard form uses this in six pairs only: IV is 4, IX is 9, XL is 40, XC is 90, CD is 400 and CM is 900. Every other letter is simply added.
How do you write numbers in Roman numerals?: Write a number in Roman numerals one place value at a time, from the biggest down. Split 386 into 300, 80 and 6. Then write each part: 300 is CCC, 80 is LXXX and 6 is VI. Join them in that order to get CCCLXXXVI. A 4 or a 9 in any place needs a subtracting pair, as in 94, which is XCIV.
What is the easiest way to learn Roman numerals?: The easiest way to learn Roman numerals is to master the seven letters first and the rules second. C is the first letter of the Latin word centum, a hundred, and M of mille, a thousand. The letters for five are halves: V is half of X, L is half of C, and D is half of M. After that, reading is mostly adding.
Why does my child write IIII instead of IV?: Many children write IIII because they have seen it on clock faces, where four is often shown that way, and four ones feel logical. The standard form is IV, and only IV counts as a correct answer in the game. One rule settles it: the same letter never appears more than three times in a row, so 4 must be IV.
Is this Roman numeral game free for a whole class?: Yes, all six levels are free for a whole class, right in a browser, with nothing to download and no accounts. For Roman numeral practice at the board, write 1 to 30 in three rows of ten. Pupils spot that the endings I to IX return after X in the second row and after XX in the third. Then each pupil takes a tablet and plays. The schools plan adds per-student pricing and a teacher dashboard of who is improving.

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