That's a classic, see for instance perl floating number addition and following discussion.

Especially Humans have too many fingers! :)

In short, the internal representation of numbers is in binary system, which can't do all decimal fractions without rounding error.

Cheers Rolf
(addicted to the Perl Programming Language and ☆☆☆☆ :)
Je suis Charlie!

In reply to Re: printf rounding issue by LanX
in thread printf rounding issue by vishy_acts

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