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tranthanhducthien
2 năm trước
Giải bài toán bằng cách lập hệ phương trình Vào thế kỷ thứ III trước Công nguyên , vua xứ Siracusa giao cho Archimèdes kiểm tra xem chiếc mũ bằng vàng của nhà vua có bị pha thêm bạc hay không. Chiếc mũ có trọng lượng 5 Newton ( theo đơn vị hiện nay ), nhúng trong nước thì trọng lượng giảm 0,3 Newton. Biết rằng khi cân trong nước , vàng giảm 1/20 trọng lượng, bạc giảm 1/10 trọng lượng. Hỏi chiếc mũ chứa bao nhiêu gam vàng, bao nhiêu gam bạc ? ( Biết rằng vật có khối lượng 100 gam thì có trọng lượng 1 Newton )
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