Answer:
[tex]\boxed{10 elements}[/tex]
Step-by-step explanation:
[tex]n(P) = 22[/tex]
[tex]n(Q) = 28\\[/tex]
n(P∪Q) = 40
Using Formula
n(P∪Q)=n(P)+n(Q)−n(P∩Q)
For, n(P∩Q), it becomes
=> n(P∩Q)=n(P)+n(Q)−n(P∪Q)
So,
=> n(P∩Q) = 22+28-40
=> n(P∩Q) = 50-40
=> n(P∩Q) = 10 elements
