Question

A geography teacher lists 12 South American countries on the chalkboard. She asks each student in her class to write a report comparing 4 of the countries. How many ways are there to select 4 of the 12 countries

Answer 1

Each student will always start with 12 choices. Once they've chosen one they will have 11 choices, then 10, then 9

So total, there are 12*11*10*9 different ways to select 4 countries from 12 countries total