This link's numbering system seems sketchy.
I note it said Queensland has "eleven and a half" public holidays. Its description then mentions two separate half-day holidays, one for Christmas Eve and "a half-day in August for the Royal Queensland Show". Two halves can't result in a whole... And anyway, the Ekka holiday isn't a half day. It's a whole day off.
Using the Victorian Government's website, I count 13 holidays in Vic. In Queensland, I count 12.5. I haven't looked at the other states, but someone probably should, to get a more reliable result.