If U is the universal set with 100 element; A and B are two set such that n(A)=50, n(B)=60, n(A ∩ B)=20, then n(A′ ∩ B′)=
If A and B are two sets such that n(A) = 70, n(B) = 60, n(A∪B)= 110, then n(A∩B) is equal to
Let U be the universal set containing 700 elements. If A, B are sub-sets of U such that n (A) = 200, n(B) =300 and n(A∩B)= 100. Then , n(A′∩B′)=
If there are two sets A and B such that n(¯A∩¯B)=n(A∩B). Universal set contains 'x' elements. Then n (A) + n (B) is