# Variation combination probability

I'm trying to calculate combination or different amount of variation we can have. E.g subway have 37 million different variations of sandwiches. I'm trying to calculate similar maths for my burger joint and want to know how many combination or variation of burger I have.. 3 different meat 9 different cheese 13 different filling 6 different salad 12 different sauce

Your able to pick 1., 2 or all 3 meat Also 1,2,3 or all cheeses together and so on..

I would be grateful if anybody can help Thanks

• If you have $k_1$ items of type 1 and you can pick any number of them, including none or all, and $k_2$ items of type 2 and you can pick any number of them, including none or all, the total number of ways to choose is $2^{k_1}2^{k_2}$, where $2^{k_1}$ is the number of subsets of the type 1 items (including the empty set) and similar for $2^{k_2}$. – Michael Feb 12 at 4:55