FWIW Perl 6 solves this problem by doing math in rational numbers by default: 

$ perl6 -e 'say -53.80 + 46.70'
-7.1

[download]

See also: What Every Computer Scientist Should Know About Floating-Point Arithmetic and rats and other pets.

Perl 6 - second systems done right

In reply to Re: Bad math by moritz
in thread Bad math by elfpen

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