Midrash for Numbers 28:29

6) (Vayikra 23:19) ("And you shall offer one kid of the goats as a sin-offering and two one-year old lambs as a sacrifice of peace-offerings.") "And you shall offer one kid of the goats as a sin-offering": I might think that the seven lambs and the kid of the goats mentioned in Bamidbar (Bamidbar 28:27, Bamidbar 28:29) are the same as those mentioned here. But when you come to bullocks and rams, you find that they are not so. (For here it is written "one year bullock and two rams," and there (Bamidbar 28:27) "two young bullocks" and "one ram.") But these are sacrificed because of the bread, and the others, because of the (festival) day.