Let S = {1, 2, 3, ...., m}, m>3. Let X1, X2, ..., Xn be the subsets of S each…

Let S = {1, 2, 3, ...., m}, m>3. Let X1, X2, ..., Xn be the subsets of S each of size 3. Define a function f from S to the set of natural numbers as, f(i) is the number of sets Xj that contain the element i. That is, f(i) = |{j | i ϵ Xj}| then