While that’s literally what it is, that’s not really how it’s represented and requires also understanding binary numbers.
Even knowing that, I’ve always found it easiest to get to the permissions the way I described, which when you think about it is actually the same as what you’d do to translate binary into decimal/octal if you don’t have them memorized: look at the values of each position that’s set to 1 and add them together. So, 101 in binary would be 4+0+1, or 5, which is the same as saying read is 4 and execute is 1 and add them together, the latter of which I think is easier to learn (and is how I’ve always seen it taught, though clearly YMMV)