Question

Let A and B be two sets such that n(A) = 75, M(B) = 65 and n(A ∩ B) = 45, find: n(A - B)

Answer 1

n(A) = 75, n(B) = 65 and n(A ∩ B) = 45

We know that,

n(A – B) = n(A) – n(A ∩ B) n(A – B)

= 75 – 45 = 30