Let X be the universal set for sets A and B. If n(A)=200,n(B)=300 and n(A∩B)=100, then n(A′∩B′) is equal to 300 provided n(X) 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′)=