Division by 3 trick - Explained!

There's a trick which says: to check if a number is divisible by 3, just add up the digits, and see if the digits are divisible by 3. Why does this trick work? In this video, we explain exactly what's going on. Most math teachers don't know why this works, so come learn why!

Видео Division by 3 trick - Explained! канала Simple Math