CMAT 2020 Solved Question Paper

Let people have brown hair = A
and people have brown eyes = B
Then, n(A) = 40%, n(B) = 30%, n(A ∩ B) = 12%
∴ n(A ∪ B) = n(A) + n(B) – n(A ∩ B)
= 40 + 30 – 12
= 70 – 12 = 58%
∴ The number of people in town have neither brown hair nor brown eyes
= 100 – n(A ∪ B)
= 100 – 58 = 42%.