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    Question

    Speed of a boat in still water is 48 km/h and the speed

    of stream is 25% of the speed of boat in still water. If the time taken by boat to cover a distance 'D' km in downstream is 2 hours less than the time taken by boat to cover the same distance in upstream, then find the value of 'D'.
    A 360 Correct Answer Incorrect Answer
    B 270 Correct Answer Incorrect Answer
    C 180 Correct Answer Incorrect Answer
    D 540 Correct Answer Incorrect Answer

    Solution

    Speed of stream = 0.25 X 48 = 12 km/h Upstream speed = 48 - 12 = 36 km/h Downstream speed = 48 + 12 = 60 km/h ATQ: We have, (D/36) - (D/60) = 2 Or, (5D - 3D) ÷ 180 = 2 Or, 2D = 360 So, 'D' = 180 Therefore, the value of 'D' is 180.

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