9 mountain bikers are on bicycle trip in how many possible ways can they follow each other

We could have 9 ways to pick the leader x 8 ways to pick the second place rider x 7 ways to pick the third place rider, etc.

So

9 x 8 x 7 x ... x 3 x 2 x 1 = 9! = 362880 ways to arrange them

Ok one way is slot method

9 slots

1st slot-9 possible people

2nd slot - 8 people (1 went to 1st slot

3rd slot-7

4th - 6

5th - 5

6th - 4

7th - 3

8th-2

9th-1

so multiply them

9*8*7*6*5*4*3*2*1 = 362880

362,880 ways