Let A, B, and C be subsets of a universal set U and suppose n(U) = 200, n(A) = 23, n(B) = 25, n(C) = 29, n(A ∩ B) = 7, n(A ∩ C) = 9, n(B ∩ C) = 14, and n(A ∩ B ∩ C) = 4. Compute:

(a) n[A ∩ (B ∪ C)]

(b) n[A ∩ (B ∪ C)c]

1 answer

I suggest using a Venn diagram, all fields of the circles can be easily filled in.
Start with the intersection: n(A ∩ B ∩ C) = 4 , then do the doubles, etc

for b) , what is the meaning of c in n[A ∩ (B ∪ C)c] ?