SETS 3

If n(B)= 90 , n(AuB)=110, n(AnB)=50, find n(A).

Solution

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

     110 = n(A)  + 90 - 50

     110 = n(A)  + 40      

     110 - 40 = n(A) 

      70 = n(A) 

Hence n(A) = 70 answer

TRY THIS…………………

If n(B)= 88 , n(AuB)=107, n(AnB)=52, find n(A).