There are 4 letters, 4 envelopes. In how many ways can wrong choices be made?

• 4 letters can be stored inside 4 envelops in 4! ways. There is only one instance, when all 4 letters are stored in their own respective (correct) envelops. All other instances are wrong choices. Hence, the required count of wrong choices = 4! - 1
• 9 years agoHelpfull: Yes(3) No(0)