Yes, it’s just roundoff errors. Because floating-point arithmetic may accumulate roundoff errors on every operation, it doesn’t follow the ordinary rules of algebra exactly in general. For example, it isn’t associative:
julia> (5 * 1) / 3
1.6666666666666667
julia> 5 * (1/3)
1.6666666666666665
This is isn’t specific to Julia, but has to do with how computers do arithmetic: see PSA: floating-point arithmetic
PS. I reformatted your post to quote your code to make it easier to read. In the future, see PSA: how to quote code with backticks