Предмет: Математика, автор: Лизоа

Три озера имеют общую площадь 32 га ( гектара ). Площадь первого озера в 4 раза больше площади второго, а площадь третьего озера 7 га. Найдите площадь первого озера.

Ответы

Автор ответа: вася1113

пусть площадь второго - х, тогда
х+4х+7=32
5х=25
х=5
5*4=20 - площадь первого озера

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