"A person write 4 letters and addresses 4   envelopes. If the letters are placed in the
Channel: Doubtnut
Date: 2020-07-05

"A person write 4 letters and addresses 4
 
  envelopes. If the letters are placed in the envelopes at random, then the
 
  probability that all letters are not placed in the right envelopes, is
 a. 1/4Â Â Â Â Â Â Â Â Â Â 
 
  b. 11/24Â Â Â Â Â Â Â Â Â Â Â c.
 
  15/24Â Â Â Â Â Â Â Â Â d. 23/24"