Ok, yours and UB’s first argument: “If it ends, it ends in a 9.” Second argument: “If it doesn’t end, it’s 9999.. on and on.”
Pick one, first of all, does it end or doesn’t it? Next, if it ends and ends in a nine then it definitely doesn’t equal 1. (I think we can all agree on that.) If it doesn’t end and has 9’s forever, then it only gets closer and closer to 1, but never reaches 1.
And yeah, yeah, yeah.. I’ve heard the whole divided by 10 and 1/3 stuff before.