How many different groups of 7 students can you create from a class of 20 students?

How many different results could there be for 10 political candidates running for the same office in the upcoming election?

2 answers

number different? 20!/7!13!

There can only be 10 different results, only one person can win
There can only be 10 different results, only one person can win.

how would i set this up?