Question

If n(A) = 5 and n(B) = 10 , then find maximum and minimum possible values of n(A ∩ B) if
(a) n(U) = 8
(b) n(U) = 20
Also explain the answer.

Answer 1

Answer:

Answer

Set A has 7 elements & set B has 8 elements.

Minimum A∪B elements condition: Out of 8 elements of set B, 7 elements are identical to that of set A. In this case A∪B=B & it will have 8 elements.

Maximum A∪B elements condition: A & B are disjoint sets, that no element will be common to them. Then:

n(A∪B)=n(A)+n(B).

A∪B has 15 elements.