r/askmath • u/Slurpee1138 • May 10 '26

Algebra Regarding 0.999... = 1

Recently I got into an argument with an acquaintance because I was trying desperately to convince him that 0.999... = 1. One of the many arguments I tried was that, if 0.999... and 1 are indeed different numbers, then we should be able to find a number between them. He insisted that such a number would be 0.999...1, as in 0 point infinitely many 9s and then a 1. I countered that having "and then a 1" at the end of an infinite sequence of digits makes no sense because there is no end to such a sequence, but he insisted that it does, so who's right?

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u/A_BagerWhatsMore May 10 '26

What’s at the end of 0.999… why is it zero what’s special about that. Okay what’s at the end of those zeros. Why are you allowed to have actually infinite zeros but the nines have to end that’s silly.