Q5 of 71 Page 30

If n(A) = 26, n(B) = 10, n (A ∪ B) = 30, n(A’) = 17, find n(A ∩ B) and n(U).

Given, n(A) = 26, n(B) = 10, n (A ∪ B) = 30 and n(A’) = 17.


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


30 = 26 + 10 – n(A ∩ B)


n(A ∩ B) = 36 – 30 = 6


Using the result n(A) + n(A’) = n(U)


26 + 17 = n(U)


n(U) = 43


So, n(A ∩ B) = 6 and n(U) = 43.


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