SETS B11

If n(B)= 60 , n(AuB)=70, n(AnB)=25, find n(A).

Solution

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

     70 = n(A)  + 60 - 25

     70 = n(A)  + 35  

    

     70 - 35 = n(A) 

      35 = n(A) 

Hence n(A) = 35 answer

TRY THIS……………………

If n(B)= 53 , n(AuB)=97, n(AnB)=40, find n(A).