Henry's Hamburger Heaven offers its hamburgers with the following condiments: ketchup, mustard, mayonnaise, tomato, lettuce, pickles, cheese, and onions. A customer can choose one, two, or three meat patties, and any collection of condiments. How many different kinds of hamburgers can be ordered?
Here is my take
3 choices of patty 3 x
9 choices of condiment (I included NO condiment) = 9!
3 x 9! =.......
I submitted it as an answer, and it said it was wrong.