Possible combinations of numbers?

[orangeincup]

Homework Statement

Assuming 10 people pick a number between 1-120 and no two numbers can be the same, how many combinations of numbers can their be?

Homework Equations

C=N^s

The Attempt at a Solution

So I know the total possible for 120 would be just 120^10, but if I want to solve for the numbers never repeating in a sequence I'm not sure how.

 

[ShayanJ]

The first guy picks one number from 1 to 120. So he has 120 choices. But the second guy has 119 choices because one number is taken by the first guy. Similarly the third guy has 118 choices. And so on.