'Fifteenth' in the Bible

And on the fifteenth day of the same month is the feast of unleavened bread; for seven days let your food be unleavened bread.

Say to the children of Israel, On the fifteenth day of this seventh month let the feast of tents be kept to the Lord for seven days.

But on the fifteenth day of the seventh month, when you have got in all the fruits of the land, you will keep the feast of the Lord for seven days: the first day will be a Sabbath, and the eighth day the same.