Authen::PluggableCaptcha::Challenge::DoMath(3)

This is a type string captcha.

You have to type a string.

Number::Spell
    Perl extension for spelling out numbers
    http://search.cpan.org/~lhoward/Number-Spell-0.04/Spell.pm

Lingua::EN::Numericalize
    Replaces English descriptions of numbers with numerals
    http://search.cpan.org/~ecalder/Lingua-EN-Numericalize-1.52/Numericalize.pm

Lingua::EN::WordsToNumbers
    convert numbers written in English to actual numbers
    http://search.cpan.org/~joey/Lingua-EN-Words2Nums-0.14/Words2Nums.pm
    http://search.cpan.org/~emartin/Lingua-EN-WordsToNumbers-0.11/lib/Lingua/EN/WordsToNumbers.pm