Question
A boat covers 4 km upstream and 15 km downstream in 7 hours, while it covers 16 km upstream and 35 km downstream in 23 hours. What is the speed of the current?
The correct answer is
2 km/hr
Let the speed of the boat be B km/hr and the speed of the current be C km/hr. - Upstream speed = (B - C) km/hr and downstream speed = (B + C) km/hr. - From the given data: (4/(B - C)) + (15/(B + C)) = 7 and (16/(B - C)) + (35/(B + C)) = 23. Solving these equations, we find that the speed of the current (C) is 2 km/hr.
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Important Questions from Boat and River
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