Q. Five persons $A,\ B,\ C,\ D\ and\ E$ are in queue of a shop. The probability that $A\ and\ E$ always together, is
A) $\frac{1}{4}$
B) $\frac{2}{3}$
C) $\frac{2}{5}$
D) $\frac{3}{5}$
Explanation
(c)
$\because Total\ number\ of\ ways = 5!$
and favourable number of ways $= 2 \bullet 4!$
$Hence,\ required\ probability = \frac{2 \bullet 4!}{5!} = \frac{2}{5}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.