Ice cream

Annie likes ice cream. In the shop are six kinds of ice cream. How many ways can she buy ice cream in three scoops if each has a different flavor mound and the order of scoops doesn't matter?

Correct answer:

n =  20

Step-by-step explanation:

$$\begin{gathered} C_3(6)=\left(\genfrac{}{}{0ex}{}{6}{3}\right)=\frac{6!}{3!(6-3)!}=\frac{6\cdot 5\cdot 4}{3\cdot 2\cdot 1}=20 \\ n=\left(\genfrac{}{}{0ex}{}{6}{3}\right)=20 \end{gathered}$$

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