Question

Let the universal set S have 146 elements A and B are subsets of S set A contains 96 and elements and set B contains 48 elements if sets A ans B have 24 elements in common how many elements are in a but not in b

Answer 1

Given that:

n(S) = 146, n(A) = 96, n(B) = 48

$n(A\cap B)=24$

Find

$n(A\cap B^C)$

$\begin{gathered} n(A\cap B^C)=n(A)-n(A\cap B) \\ =96-24 \\ =72 \end{gathered}$