Предмет: Алгебра, автор: Люцеферия

Первая труба наполняет резервуар на 21 минуту дольше чем вторая обе трубы работая одновременно наполняют этот же резервуар за 10 минут за сколько минут наполняет этот резервуар одна вторая труба

Ответы

Автор ответа: GlebGor1998

1 час= 60 мин ; 21 мин = 21/60 = 7/20 час ; 10 мин = 1/6 час
х - объем резервуара
х/ 7/20 = 20х/7 - часовая производительность первой трубы
х / 1/6 = 6х - часовая производительность обеих труб при работе вместе
Найдем часовую производительность второй трубы : 6х - 20х/7 = 42х/7 - 20х/7 = 22х/7 . Вторая труба заполнит резервуар за : х / 22х/7 = 7/22 часа или примерно за 19 минут

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