In translating 1 Kings 7, we want to use fractions when we give the number as numerals, e.g. in 7:10:

Aitoka sae ale ateva laghe atoka siola namungaili atu, kasina aluseaane erooroo kotolu me tapirina ateva (3½) mita me kasina aluseaane erooroo ghaata me tapirina ateva (4½) mita.

However, this is flagged as having number errors, with "Invalid number". I can't see how to indicate that this should be valid apart from denying the error. If I go to the Number Settings dialog for the project, the list of what can be part of a number is assumed to be 0-9 plus decimal points and thousands separators, plus punctuation. There doesn't seem to be a way to say that fractions can be numbers. Is there some further setting that I have missed?