Question 353273

No. of owners having any one of these pet = 51 - 3 = 48

thus  n(A U B) = 48 , no. of owners having any pet
  
    n(A) = 32 , no. of owner having dogs

    n(B) = 38 , no. of owner having cats


now we have to find no. of owners having cats and dogs n (A∩B)

as we know  n (A∩B) = n(A ) + n (B) - n(A U B)



 = n(A ) + n (B) - n(A U B)

 = 32 + 38 - 48 

 = 22