SETS B20

If n(B)= 60 , n(AuB)=90, n(AnB)=25, find n(A).

Solution

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

     90 = n(A)  + 60 - 25

     90 = n(A)  + 35      

     90 - 35 = n(A)

 

      55 = n(A) 

Hence n(A) = 55 answer

TRY THIS…………………..

If n(B)= 63 , n(AuB)=96, n(AnB)=27, find n(A).