This formula makes perfect sense to me looking at the C Major chord but when I look at the A Major chord I'm kind of lost. If you look at the picture example in the lesson the A Major chord follows this pattern of the scale 1,5,1,3,5.
I was under the impression the formula is to be as followed 1,3,5,1,3 as it is clear in the C Major chord.
Maybe this is a simple solution and could answer my own question do you have to use the triad in that specific order or can you choose to put them in any random order and get a correct result?