Question

Let A and B be two finite sets such that n(A)=20,n(B)=28 and n(AUB)=36,find n(A∩B)

Answer 1

answer is Null vector

Answer 2

we know that n(AorB)=n(A)+n(B)-n(A&B)
putting these values
20+28-n(A&B)=36
n(A&B)=-36+48=12
Hope it will help you