Предмет: Математика, автор: daratimofeeva899

ученик прочитал 50 страниц книги, и осталось прочитать ещё 20 страниц, какую часть книги прочитал ученик​

Ответы

Автор ответа: ludmilaksenija2005
0

Пошаговое объяснение:

50+20=70 стр всего

Пропорция :

70 стр - 1 часть

50 стр - х частей

Х=50×1:70=5/7 части прочитал

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