SETS B21

If n(B)= 70 , n(AuB)=100, n(AnB)=25, find n(A).

Solution

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

    100 = n(A)  + 70 - 25

     100 = n(A)  + 45  

    

     100 - 45 = n(A) 

      55 = n(A) 

Hence n(A) = 55 answer

TRY THIS…………………..

If n(B)= 66 , n(AuB)=98, n(AnB)=29, find n(A).