# Thread: formula for possible options

1. ## formula for possible options

Isn't there a formula that will tell me the number of possible 3 course selections out of a population of 5 courses? Seems like writing down all the different options and then counting them is a waste of time, but I haven't been able to find the formula.

2. ## Re: formula for possible options

You are probably talking about combinations.

3. ## Re: formula for possible options

n choose k = $\frac{n!}{k!(n-k)!}$

thank you!