'Fifteen' in the Bible

You shall till the land for him, you and your sons and your servants; you shall bring [in the produce] and it shall be food for the son of your master that he may eat. But Mephibosheth the son of your master may always eat food at my table." (Now Ziba had fifteen sons and twenty slaves.)

and a thousand men [were] with him from Benjamin. Too, Ziba the servant of the household of Saul and fifteen of his sons and twenty of his servants [were] with him, and they rushed to the Jordan before the king.