This question comes up regularly on Perlmonks. In fact, back when I was a novice Monkling, I actually asked (a variant of) it myself *blush* at (s)printf and rounding woes.

It also, of course, regularly comes up on forums for other languages, since such phenomena are not restricted to perl.

For the best explanation I have yet to find, please read this: Re: Re: Re: Bug? 1+1 != 2, by BrowserUK

In reply to Re: strange result for a simple addition ?? by Not_a_Number
in thread strange result for a simple addition ?? by Marsel

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