- #1
kashan123999
- 98
- 0
Homework Statement
A notorious postman delivered 4 letters to four houses in such a way that no house will get the correct letter...in how many ways he delivered the letter ? Please explain it
Homework Equations
I think this is permutation question...using fundamental law of counting
The Attempt at a Solution
I don't know where to start,i think they can be delivered in 7 ways cause first letter will be delivered in 3 ways,because 1 house is correct..after that 2nd letter can be arranged in 2 ways...3rd and 4th in 1 1 way..so 3+2+1+1=7 ways...