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Topic: how does .9999999=1???
Replies: 19   Last Post: Jan 1, 2011 2:43 AM

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Posts: 11
Registered: 9/29/10
Re: proof for .9999999=1
Posted: Dec 27, 2010 11:46 AM
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On Sun, 26 Dec 2010 08:14:02 EST, in article
jay kirschbaum wrote:
> This discussion is pretty old but I am looking for more proofs beyond the convincing one I learned in high school -
> If .333333.... = 1/3
> and .333333.... x 3 = .9999999......
> and 1/3 X 3 = 1
> then .99999..... = 1

For a general discussion and a few informal proofs, see:

For an indisputable formal proof, see:


"You're at the bottom of the class. Lots of verbiage but the
mathematics escapes you." -- James S. Harris

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