Answer:
6
Step-by-step explanation:
We have 3 items (n = 3),
Appetizers = A
Main course = M
Dessert = D
which can be ordered in 6 different ways. The problem is solved by thinking it as a permutation of 3 elements.
The formula for that is:
P = n!
P = 3! = 3 x 2 x 1 = 6
Let's see check it:
AMD
ADM
MAD
MDA
DMA
DAM