Предмет: Химия, автор: grosmtsd4

Какой объем воздуха содержит 390 литров азота? (Учитывать процентное содержание азота в воздухе).

Ответы

Автор ответа: mashilda342

500 литров

Решение:
390-78%
х-100%

про пропорции решаем получается 390/0,78=500

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