Question

Let A and B be two sets such that

$n ( A ) = 0.16 , n ( B ) = 0.14 , n ( A \cup B ) = 0.25$

Then $n ( A \cap B )$ is equal to

• A. 0.3
• B. 0.5
• C. 0.05
• D. None of these

Answer 1

Answer: (C)

0.05

Answer 2

$n ( A \cup B ) = n ( A ) + n ( B ) - n ( A \cap B )$

$0.25 = 0.16 + 0.14 - n ( A \cap B )$

⇒ $n ( A \cap B ) = 0.30 - 0.25 = 0.05$.