Question

There are 5 letters and 5 addressed envelopes. if the letters are put atrandom in the envelops, the probability that all the letters may be placed inwrongly addressed envelopes is.

Answer 1

So,

This is indeed a good question

Since, this is theory of dearangement , the arrangement where none of them go to proper places is given by approximately

(n!)/e

D= n! (1 -1/1! + 1/2! - 1/3! -..)

D=44

So,

Probability= 44/5!

=11/30

Hope this helps!!!!!!!!!