Punishment 26851

Alena, Ivana, Edo, Filip, and Martin came late to school. As a punishment, two will water flowers all over the school after class, and the other three will clean up the classroom. The class teacher couldn't decide who to send to water the flowers, so Juro started listing all the options for her. Complete his solution.

Correct answer:

n =  10

Step-by-step explanation:

$$\begin{gathered} C_2(5)=\left(\genfrac{}{}{0ex}{}{5}{2}\right)=\frac{5!}{2!(5-2)!}=\frac{5\cdot 4}{2\cdot 1}=10 \\ n=\left(\genfrac{}{}{0ex}{}{2}{5}\right)=10 \end{gathered}$$

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