Why does the Torah see fit to state the total number (10) of bulls, rams, lambs of the Olah and the Minchah that the Nesi'im donated?
Targum Yonasan: The twelve bulls came to symbolize the twelve princes, the twelve rams, the twelve princes of Yishmael who will be destroyed, the twelve lambs, the twelve princes of Persia that will be destroyed, the twelve goats came to atone for the sins of the twelve tribes, and their Menachos to symbolize the famine that will come to an end. 1
See Na'ar Yonasan.
And why does it see fit to state the total number of goats of the Chatas?
Targum Yonasan: And the twelve goats of the sin-offering come to atone for sins of the twelve tribes.