Swiftprep - Multiplication: the "choice" method

I am confused about the notes in this video about the question around 6 minutes. The note says there are 10 ways of choosing an ice cream without a topping. However, the question says that the customer MUST get at least 1 topping. Wouldn’t this mean that choosing an ice cream without a topping is not an option?

Correct, and in how many ways can we do that?

Got it! thank you