Acatering service offers 12 appetizers, 4 main courses, and 8 desserts. a banquet chairperson is to select 9 appetizers, 2 main courses, and 7 desserts for a banquet. in how many ways can this be done

We know this is a combination with no repeats, because order does not matter.
This is the formula for that:

(n is the number you have to choose from, and r is the amount you are choosing)
To make this go faster, I'll be doing all the work on paper and insert a photo of it.
The first part of this is me going through the work. I used a calculator to assist with multiplication and division.
 We'll now find out how many different combinations can be made in total.
See my paper to see what I do. The rest of my answer is listed there.