1. The problem statement, all variables and given/known data If n(A - B) = 5, n(A' - B) = 4, n(A') = 10, n(B'-A') = 12. What is n(AUB) = ? 2. Relevant equations 3. The attempt at a solution I drew a big rectangle and inside 2 intersected diagrams A and B. I drew 5 dots in the (( of diagram A. Now that A' is complementary that means they have nothing in common, so I drew 5 dots outside of the diagrams(inside the rectangle). n(B' - A') = 12. If A' = 10. B' = 2? About the question above. NOTHING else is given, just that.