Question

11. If n(A)= 11, n(B) = 7, n(AUB) = 13, then
AB= ?
(A) 5 (B) 6 (C) 7 (D) 2​

Answer 1

Answer:

5

p(AUB)=p(A)+p(B)-p(AB)

13=11+7-p(AB)

13=18-p(AB)

p(AB)=18-13

p(AB)=5