3. Number of elements in the union of sets

If \(n(A) = 54\), \(n(B) = 29\), \(n(C) = 27\), \(n(A \cap B) = 17\), \(n(B \cap C) = 19\), \(n(A \cap C) = 19\), and \(n(A \cap B \cap C) = 7\), then find out \(n(A \cup B \cup C)\).

 

\(n(A \cup B \cup C)\) \(=\) .