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In the opening for mathematics fair, 3 students out of the 20 participants will be chosen to sing the national anthem, to lead the invocation, and to introduce the guest speaker. How many ways can the 3 students be chosen?

Respuesta :

Given that there are 20 participants and only 3 students to choose to. The number of ways the 3 students can be chosen is

[tex]\begin{gathered} _{20}C_3=\frac{20!}{3!(20-3)!} \\ _{20}C_3=\frac{20!}{3!\cdot17!} \\ _{20}C_3=1140 \end{gathered}[/tex]

Therefore, there are 1140 ways the 3 students can be chosen.

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