Here are a couple of links to answer your question:

Bug? 1+1 != 2 (be sure to read Re: Re: Re: Bug? 1+1 != 2 for a good explaination)

What Every Computer Scientist Should Know About Floating-Point Arithmetic

and a current thread alond the same lines: Math 101 anyone?

-enlil

In reply to Re: Strange rounding Error in Perl by Enlil
in thread Strange rounding Error in Perl by kju

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