Mixing Letters and Numbers

Sometimes we save space, or typing, by using a number with a suffix:

57th Street

That’s perfectly legitimate, and for larger numbers it’s probably easier to read than spelling the whole thing out:

Fifty-Seventh Street

But we do have to be careful to remember that both the numbers and the letters represent sounds. The number “20” is pronounced “twenty,” for example. So what do we make of this?

A porch near the New Hamburg train station in New York is occupied by strange mannequins dressed in 20ies fashion.

There are many people who absorb information from written text without ever hearing the sounds of the words, and perhaps they won’t see anything wrong with that. But if you were to read that sentence out loud, actually reading all the characters the writer has put in it, this is what you would say:

A porch near the New Hamburg train station in New York is occupied by strange mannequins dressed in twenty-eez fashion.

When you make a number plural, just add an S to it. That’s enough, and anything more is too much.

We have to be similarly careful about making ordinal numbers—like “57th,” for example. That’s fine, but what would you say to these?

The 51th Annual Golden Apple Awards

51th Meeting of the UNWTO Commision for Europe

51th Anniversary Meeting of the Clay Minerals Society

The Editor found “About 473,000 results” for “51th” on Google. But we don’t say “fifthy-oneth.” We say “fifty-first.” That little “th” is wrong, and rather funny to someone who actually hears the sounds of words.


52th meeting of IPDC Bureau

52th WWC Board of Governors Meeting

52th Commonwealth Parliamentary Conference

…and about 233,000 other results for “52th.” We say “fifty-second,” not “fifty-twoth.” Shall we try our luck with 53?

53th District of California

53th anniversary of the Berlin Wall

Kirklin takes charge of Corps, named 53th QM General

We say “fifty-third,” not “fifty-threeth.”

For numbers that end in 1, 2, or 3, adding “th” to the end won’t work. Here’s how to add the right suffixes:


52nd or (less common) 52d

53rd or (less common) 53d.

But wait! Don’t those suffixes violate the fundamental rule above—namely that both the number and the letters are pronounced?

Yes, they do. Life isn’t always fair. We don’t say “fifty-twond.” We’re stuck with the fact that the ordinal numbers first, second, and third are completely different words from the cardinal numbers one, two, and three. But these suffixes are the traditional way of abbreviating those ordinal numbers, so we don’t provoke snickers from the audience.

Fractions with Whole Numbers

Be careful when writing fractions after whole numbers, like 1½. They may not print correctly when your writing is published. From a newspaper article about flooding in Pittsburgh:

But, again, to have 11/2 to 2 inches of rain fall in such a short period of time…

The reporter meant “1½,” not “11/2,” which is obviously equivalent to 5½.

If you can’t be sure that fractions will appear properly in the final publication, there are two ways around the problem:

1. Use decimals: “1.5” instead of “1½.”

2. Especially in direct quotations, spell out the fraction: “1 and a half” instead of “1½.”

Roman Numerals: How They Work

Update: A kind reader pointed out a sloppy error in the explanation of subtractive notation below. That section has been corrected, and many thanks for the correction.

Having already advised everyone to avoid Roman numerals when it’s possible to do so, the Editor now gives you a short instruction manual for using them, in case you should have to scribble out a cornerstone on a moment’s notice.

The first thing to know is that there isn’t just one set of rules for Roman numerals. Though Arabic numerals have long supplanted them for most practical uses, the use of Roman numerals has continued to evolve and change right up through our own generation. But since Roman numerals are still in use precisely because they’re a relic of the past, it’s quite correct to use Roman numerals from any stage in their development.

Roman numerals, as you know, use letters to represent numbers:

I = 1
V = 5
X = 10
L = 50
C = 100
D = 500
M = 1,000

There are ways of expressing millions and billions in Roman numerals, but in practice you will never need to use Roman numerals for any number higher than the current year.

A number is created by addition, largest numeral to smallest. For example, 2 is II (1 + 1), and 7 is VII (5 + 2). And so on:

LXVII = 50 + 10 + 5 + 1 + 1 = 67
MMX = 1,000 + 1,000 + 10 = 2,010
DXI = 500 + 10 + 1 = 511

That’s the first rule. When you see a larger number followed by an identical number or a smaller number, you add them together.

But there’s a complication. No more than three identical numerals in a row are allowed. VIII is all right, but not VIIII. So we have the second rule: when you see a smaller number preceding a larger number, you subtract the smaller number from the larger number:

IX = 10 – 1 = 9
XL = 50 – 10 = 40
XCVI = (100 – 10) + 5 + 1 = 96
XLIV = (50 – 10) + (5 – 1) = 44
MCMXCIX = 1,000 + (1,000 – 100) + (100 – 10) + (10 – 1) = 1,999

There can be only one subtracted numeral, so we can’t write IIX for 8. Only I, X, and C can stand before a larger numeral to subtract from it, and they can’t stand in front of numerals more than ten times their value; IX for 9 is fine, but we can’t write IL for 49 or IM for 1,999—we have to write XLIX or MCMXCIX.

This means that there are only six subtractive combinations we can use, and here’s the complete list: IV, IX, XL, XC, CD, CM.

This rule of subtraction is relatively modern. The ancient Romans knew nothing of it, so they were quite happy to write VIIII for 9 or MDCCCCLXXXXVIIII for 1999. Many buildings from the early 1900s bear dates that follow this more strictly classical format, like MDCCCCIIII for 1904.

You may also run across other variants in print or in stone. An older form of the Roman numeral for a thousand is a C, an I, and a backwards C, like this: CIƆ. Many books printed in the first two centuries of printing use that form. It was also common to give Roman numerals a sort of elementary place value by dividing the orders of magnitude with periods:

M.DCC.LXX.VI = 1776

Roman numerals may, of course, be written in lower case as well as upper case, as they commonly are when used for page numbers. In many medieval manuscripts and printed books through the 1700s, the last of a series of ones is written as a j:


Clock faces have an entrenched and traditional inconsistency: the number 4 is always rendered IIII, but the number 9 is always rendered IX. The imperfectly omniscient Wikipedia explains that “Louis XIV, king of France, who preferred IIII over IV, ordered his clockmakers to produce clocks with IIII and not IV, and thus it has remained.” But an explanation that refers a universal usage or tradition to one person or event is likely to be wrong, and five minutes’ rummaging in Wikipedia debunks that myth with a clock face from well before Louis XIV’s time.