Предмет: Математика, автор: zher97

задача по комбинаторикеи,в классе 25 человек. из них требуется выбрать дежурного ,культорга и старосту . сколькими способами это можно сделать?

Ответы

Автор ответа: vita612

Простейшая задача..
Воспользоваться формулой сочетания
n
C = n!/m!*(n!-m!)
m

3
C = 13800/6 = 2300
25

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