Did you know you can subtract left to right?

Why not represent the sub-differences like so to preserve place value?

Great video. Thanks for sharing! I also appreciate the reference to James Tanton. He is truly inspirational for us math instructors. Love his thoughts on teaching trig.

I can subtract large numbers much more quickly in my head now! ❤️

I have questions for my old maths teacher. WHY DID YOU NEVER MENTION THIS?!

This makes so much more sense to me. I always subtract left to right mentally, so it’s good to see it written down like this.

Je le montrais aux 5e et ceux qui n'avaient pas trop de difficultés en calcul avec les relatifs l'utilisaient. Réinvestit les relatifs, développe le calcul mental, finies les retenues, ordres de grandeurs. Ils adoraient cela!

WHAT??? WHY didn’t anyone tell me this when I was a kid??? I LOVE this!! Thank you!! 🙌🤗💗

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