Calculate the probability of the event, when choosing a random permutation of {1, 2, ..., n}, $\displaystyle n \ge 4$.
a) with 1 front 2
b) with 2 front 1
c) with 1 stand just before 2
d) n front 1 and n-1 front 2
e) n front 1 and n front 2
Calculate the probability of the event, when choosing a random permutation of {1, 2, ..., n}, $\displaystyle n \ge 4$.
a) with 1 front 2
b) with 2 front 1
c) with 1 stand just before 2
d) n front 1 and n-1 front 2
e) n front 1 and n front 2