Найдите сумму 1 плюс 2 плюс 3 плюс........ 250 - №29357534

Найдите сумму 1 плюс 2 плюс 3 плюс........ 250
- Предмет:
  Математика
- Автор:
  avahfrey
- 6 лет назад

Ответы 1

$S_{250} = \frac{1+250}{2} *250=251*125=31375$
- Автор:
  gauge
- 6 лет назад
- 0
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