From: utzoo!decvax!harpo!npoiv!hou5f!hou5b!hou5c!hou5e!ijk Newsgroups: net.math Title: Re: .999... = 1 Article-I.D.: hou5e.216 Posted: Wed Jan 26 09:38:28 1983 Received: Fri Jan 28 07:05:27 1983 I just couldn't resist adding my 1.999... cents worth. This proof comes from 11th grade math class - a long time ago. Let x = .999... (remember that ... stands for '9' ad infinitum) then 10 * x = 9.999... subtract first line from second and we get simply: 9x = 9. (!exactly) or x = 1. IT is true. As people have pointed out, it takes an understanding of limits to really see what is going on, but it is not necessary for the proof. Just another example of the mysteries of infinity (what has more points in it: a line an inch long or a line a mile long?? Ans: they have the same).