Q. There are 5 letters and 5 different envelopes. The number of ways in which all the letters can be put in wrong envelope, is
A) 119
B) 44
C) 59
D) 40
Explanation
(b)
Required numbers$= 5!\left\lbrack 1 - \frac{1}{1!} + \frac{1}{2!} - \frac{1}{3!} + \frac{1}{4!} - \frac{1}{5!} \right\rbrack$
=44
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.