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nt_vu.c3trungan
2 năm trước
Một chiếc bè tại H và một ca nô từ K khởi hành cùng một lúc. Nếu đi cùng chiều theo hướng từ K đến H, ca nô sẽ đuổi kịp chiếc bè sau 1 giờ 45 phút ; nếu đi ngược chiều, ca nô sẽ gặp chiếc bè sau 50 phút. Hỏi vận tốc của ca nô gấp bao nhiêu lần vận tốc của chiếc bè? Biết rằng quãng đường HK có chiều dài 28km.
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