I know, I know. You’re sitting there thinking “How does that even work? Decem starts with a d, not an x.” Well, I’ll tell you.
Today we’re going to have a little Latin lesson, with the numbers 1-10. Chart, below, via Transparent Language.
As you reach number seven, you may notice that the Latin looks kind of familiar. That’s because September, October, November, and December were months seven through 10 in the ancient Roman year. The Roman numeral for 10, X, is decem.
As an aside, I learned to tell time on a clock face with Roman numerals, which hung in our living room. That’s why I included a clock on this post.