The average of a set of numbers is calculated by taking the sum of all the numbers, and then dividing by the number of terms in the set.

(1) Find the average of 2, 9, 5, 1, and 6.
(2) Find the average of 199, 225, 836, 998, 751, 154, and 423.
(3) Find the average of 1, 1, 2, 3, 5, 8, 13, 21, 34, and 55.