All classes come from some super class, you need to lookup ancestors also lookup the RUBY docs, Integer inherits methods from its superclasses.

class numeric has step method

I am new to Ruby - I'd expect the min parameter to be an integer, but the integer class doesn't have a step method. What gives?

https://ruby-doc.org/core-2.5.0/Integer.html

Still missing picture.

yup, having 1..n creates a range from 1 to n (inclusive). You can check out https://ruby-doc.com/core-2.4.7/Range.html for more info on them.

does your i in this example start at 1 due to (1..n)? Cause I use Array.new and have to use (n - 1 - i)

Very readable! Helped me reflect on my solution and see a new way of doing things. Thanks :)