NEW! After the vid, take my Roman numerals quiz on my website! Here's your link: https://www.letsdomath.ca/romannumer...

If this vid helps you, please click the LIKE button to help me too.

Roman numerals are still in use and it's cool to be able to decode them.
I give their values, then count to 20, drawing attention to the 'less than', 'more than' conventions. 30, 40, 50, 60, 70, 80, 90, 100, 200, 300, 400, 500, 600, 700, 800, 900, 1000, 2000, 3000.
Practice decoding: 3 examples, progressively more tricky with more numerals involved.
Easy access: rewrite, spacing the letter groups apart, then decode.

I used some photos with Creative Commons attributions in this film.

Tim Pierce: photographer of BostonHibernian Hall cornerstone
This file is licensed under the Creative Commons Attribution 3.0 Unported license.

Clock (Valladolid)
By dronepicr (historic watch in valladolid Mexico) [CC BY 2.0 (http://creativecommons.org/licenses/b...)], via Wikimedia Commons

Watch
By Seiko (Yeoman) [CC BY 3.0 nl (http://creativecommons.org/licenses/b...)], via Wikimedia CommonsHTML