Q. Probability $P(A) = \frac{4}{5},P\left( B^{'} \right) = \frac{2}{5}$and $P(A \cap B) = \frac{1}{2},$then$P(A \cap B')$ is equal to

A) $\frac{3}{10}$
B) $\frac{5}{2}$
C) $\frac{2}{5}$
D) $\frac{5}{7}$
Explanation

(a)
Here, $P(B) = 1 - P\left( B^{'} \right) = 1 - \frac{2}{5} = \frac{3}{5}$
$\therefore\ P(A \cup B) = P(A) + P(B) - P(A \cap B)$
$= \frac{4}{5} + \frac{3}{5} - \frac{1}{2} = \frac{9}{10}$
$\therefore\ P\left( A \cap B^{'} \right) = P(A \cup B) - P(B)$
$= \frac{9}{10} - \frac{3}{5} = \frac{3}{10}$

Dr. Abubacker
Reviewed by Dr. Abubacker

Physics Educator & NEET/JEE Specialist

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