Question

If $n(A)=12$, $n(B)=8$, $n(A\cap B)=4$, then $n(A\cup B)$ is equal to

• A. $20$
• B. $12$
• C. $16$
• D. $18$

Answer 1

Answer: (C)

$n(A\cup B)=n(A)+n(B)-n(A\cap B)$
$=12+8-4=16$.