True, but you wouldn't use that in a context where precision is required. You'd say something like '31 weeks' if the specific duration mattered, or just the da

True, but you wouldn't use that in a context where precision is required. You'd say something like '31 weeks' if the specific duration mattered, or just the date itself. When the exact duration isn't particularly relevant, the ambiguous 'four and a half months' works just fine.