Q6 of 71 Page 30

If n(U) = 38, n(A) = 16, n(A ∩ B) = 12, n(B’) = 20, find n(A ∪ B).

Using the result n(B) + n(B’) = n(U)


n(B) + 20 = 38


n(B) = 38 – 20 = 18


We have, n(A ∪ B) = n(A) + n(B) – n(A ∩ B)


n(A ∪ B) = 16 + 18 – 12


n(A ∪ B) = 34 – 12 = 22


Hence, n(A ∪ B) = 22.


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