1. The missing question here is : "what is the probability that the mail sorter placed each letter correctly"?
2. Name the letters L1, L2, ....L8 (Letter 1, Letter 2.... Letter 8)
3. The first letter has a probability of 1/25 to be placed in the correct mailbox.
Each of the remaining 7 letters have 1/25 probability, and these probabilities are related.
4. So the probability that each letter goes to the proper mailbox is
