Question

Một thuyền máy đi ngược dòng từ bến A đến bến B mất 2 giờ 30 phút.Biết vận tốc của thuyền máy khi nước lặng là 25,5km/giờ và vận tốc của dòng nước là 4,5km/giờ.Tính độ dài quãng sông AB.

Answer 1

Thuyền máy đi ngược dòng từ bến A đến bến B với vận tốc : 25,5 - 4,5 = 21 (km/giờ)

Quãng sông AB dài (2 giờ 30 phút = 2,5 giờ) : 21 x 2,5 = 52,5 (km)

Answer 2

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