Предмет: Математика, автор: maxdonakov

Нужно пробежать 3 км за 12:00
Круг-400 метров
Всего 7,5 кругов
За сколько нужно пробегать круг?

Ответы

Автор ответа: Sanyasha
1

Ответ:

1 минута 36 секунд

Пошаговое объяснение:

В одном километре 1000м, значит:

3 км = 3000 м

Узнаем, за сколько пробегаем 400м, если 3000 за 12 минут.

Составляем пропорцию:

x - 400 м

12 - 3000 м

х = (12*400)/3000 = 48/30 = 1 18/30 = 1 36/60 = 1 минута 36 секунд

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