Question

    A boat can row to a place of 60km away and come back in  hours. The time to row 12 km  with the stream is same as the time to row 8km against the stream. Find the speed of the current?

    A 4 km/hr Correct Answer Incorrect Answer
    B 10 km/hr Correct Answer Incorrect Answer
    C 3 km/hr Correct Answer Incorrect Answer
    D 2 km/hr Correct Answer Incorrect Answer

    Solution

    Speed downstream = 12/x km/hr Speed upstream = 8/x km/hr According to the question, 60/(12/x) + 60/(8/x) = 25/2 60 (x/12+x/8) = 25/2 15 (x/3+x/2) = 25/2 x = 1  So, speed downstream = 12 km/hr Speed upstream = 8 km/hr Speed of current = 1/2 (12 – 8) = 2km/hr 

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