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buithanhbinh02
2 năm trước
1) Hai xe máy khởi hành lúc 7 giờ sáng từ A để đến B . Xe máy thứ nhất chạy với vận tốc trung bình 30km/h , xe máy thứ hai chạy với vận tốc lớn hơn vận tốc của xe máy thứ nhất là 6km/h . Trên đường đi xe thứ hai dừng lại nghỉ 40 phút rồi lại tiếp tục chạy với vận tốc cũ . Tính chiều dài quãng đường AB , biết cả hai xe đến B cùng lúc 2) 2 người đi bộ khởi hàng ở 2 địa điểm cách nhau 4,18 km đi ngược chiều nhau để gặp. người t1 mỗi giờ đi 5,17 km. Người t2 mỗi giờ đi được 6,3 km nhưng xuất phát sau người t1 4 phút. Hỏi người t2 đi trong bao lâu thì gặp người t1
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