My three friends and I have dinner together every weekend. Each weekend, two of us cook and the other two clean up afterwards. How many different ways are there for us to choose who cooks and who cleans?
Sometimes....I find it helpful to make a chart
Call the people A, B, C, D
This makes sense....from any of the 4, we want to choose any 2 to cook = C(4,2) = 6
The ones who clean are defaulted by our choice of the cooks