Предмет: Математика, автор: sergeyviktorovich020

У країни між будь-якими двома мистами є

авіасполучення.скильки в країни якщо видомо що усіх авиалиний більше 70 але біільше 80 срочно пажалуйста

Ответы

Автор ответа: abaminkovasilij
0

Ответ:

Пошаговое объяснение:

(Х×(Х-1))÷2

70<(Х×(Х-1))÷2<80

140<Х×(Х-1)<160

Способом пiдбору одержуемо,що Х=13

Отже, мiст 13

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