Question 276775
Notice how there are 30 elements in the set {1, 2, 3, 4, 5,...,29, 30} by simply noting that 30-1+1=30 or that the elements are integers, start at 1 and end at 30.


Simply invert each element to get {1/1, 1/2, 1/3, 1/4, 1/5, ..., 1/29, 1/30} which is close to what we want, but we have to remove the element 1/1 to get {1/2, 1/3, 1/4, 1/5, ..., 1/29, 1/30}. Since we removed one element, we now have 29 elements in this set.


So n(A) = # of elements in set A = 29