SETS B3

If n(A)= 60 , n(B)= 50 and n(AnB)=30, find n(AuB).

Solution

n(AuB) = n(A) + n(B) - n(AnB)

            = 60 + 50 – 30

            = 110 – 30

            = 80

Hence n(AuB) = 80 answer