M and N are two subsets of the universal set (U). If n(U) = 48,…

M and N are two subsets of the universal set (U). If n(U) = 48, n(M) = 20, n(N) = 30 and n(MUN) = 40, find n(M (cap) N)

Correct Answer: Option D

Explanation

Let n(M (cup) N ) = x

Then 20 – x + x + 30

– x = n(M (cup) N)

50 – x = 40

50 – 40 = x

10 = x

x = 10

Hence, n(M (cupN)’ = 8  + (20 – 10) + (30 + 10)

= 8 + 10 + 20

= 38