Question 144537
The possibilities are 9x9x9 = 729 if you consider 3 scoops of the same flavor as a choice.
If the 3 flavors are to be different, then it's 9x8x7 = 504, but only if you consider a stack of flavors A B C to be different from A C B, that is with ordering.
If it's to be 3 different flavors and the order doesn't matter, then it's 9x8x7/6 = 84.