Q. Let $A$ and $B$ are two events and $P\left( A^{'} \right) = 0.3,\ P(B) = 0.4,\ P\left( A \cap B^{'} \right) = 0.5,$ then$P(A \cup B^{'})$ is

A) 0.5
B) 0.8
C) 1
D) 0.1
Explanation

(b)
Here, $P\left( B^{'} \right) = 1 - 0.4 = 0.6$
and $P(A) = 1 - 0.3 = 0.7$
$\therefore\ P\left( A \cup B^{'} \right) = P(A) + P\left( B^{'} \right) - P(A \cap B^{'})$
$= 0.7 + 0.6 - 0.5 = 0.8$

Dr. Abubacker
Reviewed by Dr. Abubacker

Physics Educator & NEET/JEE Specialist

Ph.D. in Physics with 19+ years of teaching experience.