I can't speak for the other 4 people, but I was taught to perform that trick in kindergarten. They even asked me which color was my favorite. Later, in high school, I learned about the difference between red and blue on the electromagnetic spectrum. And still later, in college, I learned about color perception in Psych and CompSci classes. For a while, I imagined that everyone had learned the same color facts that I had.

Then I ventured into a philosophy classroom, was exposed to G.E. Moore talking about "yellow" and "qualia", and I came to understand that not everyone had the same educational advantages I had.