Formal English rules say that an incomplete number should be written out in words.
...I think you said you made four or five hundred dollars.
Combined with the consistency rule, this presents some issues in a reporting transcript. When there are other numbers in the same sentence or area of the transcript, it is simply not practical to write
everything out in words.
An alternative is to use figures with a hyphen after them for the incomplete number.
...I think you said you made 4- or $500.
...We paid $675,000 for the house and sold it two years later for 8-.
Happy punctuating!
Margie