Possible combinations of numbers?

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SUMMARY

The discussion focuses on calculating the number of unique combinations of numbers chosen by 10 people from a range of 1 to 120, ensuring no repetitions. The formula used is based on permutations rather than combinations, specifically the product of decreasing choices: 120 choices for the first person, 119 for the second, down to 111 for the tenth. The final calculation yields 120! / (120 - 10)! as the correct method to determine the total unique combinations.

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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.
 
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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.
 

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