Question

if n(A) = 20 , n(B) = 50 , n(AUB) = 60 and n(B') = 20 , find n(A∩B) and n(U)​

Answer 1

Step-by-step explanation:

n(A∪B)=n(A)+n(B)−n(A∩B)−−−−−−−(1)

Given n(A)=7

n(B)=9

n(A∪B)=14

Substituting in 1

14=7+9−n(A∩B)

⇒n(A∩B)=16−14=2

Answer 2

n (A U B) = 14

hope it helps you