Question

If a (A)=20, n(B) = 50, n(AUB) = 60 and n (B`) = 20, find n(A u B) and n(u).
Answer the correct answer fast ​

Answer 1

Here's the answer!

Given: n(A) = 25; n(B) = 40; n (AU

B) = 50; n (B¹) = 25

Formula to be used:n (AUB) = n(A)

n (B)-n (ANB)

Substituting the given values in the above formula we get,

=> 50 = 25 + 40-n (AMB)

=> n(ANB) = 25+ 40-50 => n(ANB) = 65-50 = 15

Hence n (ANB) = 15 We also know that,

n(B ^ 1) = n(U) - n(B)

Substituting the values we get,

25 =n(U)- 40

=n(U)=40 + 25 = 65.

hence the universal set n(U) contains 65 elements