https://www.musical-u.com/learn/the-magic-number-and-how-to-use-it-to-learn-anything/
The best way to approach learning is to understand the brain processes involved.
We musicians can use this knowledge to our advantage in figuring out how to commit concepts, theory, and pieces of music to our long-term memory and be able to effortlessly recall them at will.
How does this relate to the “magic number”?
The magic number is all about the Working Memory and what it can easily hold. To better understand this, first we need to go over the basics of memory.