UPSEE Solved Model Paper 5

Since, a person can alight at any one of n floors
Therefore , the number of ways in which m passengers can alight at n floors is n × n × n × ... × n = nm - m times
The number of ways in which all passengers can alight at different floors is

n

‌

Cm×m! =

n

‌

Pm
Hence, required probability

n ‌ pm

nm