Предмет: Алгебра, автор: zharkunbekmlik2005

Кубический бассейн можно наполнить водой за 45 минут через трубу. Так сколько часов нужно, чтобы заполнить бассейн той же трубой, кубический бассейн, ребро которого в 2 раза больше чем у первого?


serd2011: Подразумевается, что объем воды за единицу времени изменится?
serd2011: Понял

Ответы

Автор ответа: serd2011
2

Ответ:

6 часов

Объяснение:

Пусть сторона бассейна была a, тогда его объем a^3

Увеличим сторону в 2 раза, теперь сторона 2a, а объем (2a)^3 = 8a^3

Объем бассейна увеличился в 8 раз, значит и время увеличится в 8 раз.

45 минут - это \frac{45}{60} = \frac{3}{4} = 0.75 часа

Т.е. времени необходимо 0.75 * 8 = 6 часов

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