Question

    The speed of a boat in still water is 10 km/hr and the

    speed of the stream is 2.5 km/hr. A man rows to a place at a distance of 37.5 km and comes back to the starting point. The total time taken by him is:
    A 8 hours Correct Answer Incorrect Answer
    B 13 hours Correct Answer Incorrect Answer
    C 9 hours Correct Answer Incorrect Answer
    D 10 hours Correct Answer Incorrect Answer
    E 14 hours Correct Answer Incorrect Answer

    Solution

    Rate downstream = (10 + 2.5) kmph = 12.5 kmph Rate upstream = (10 – 2.5) kmph = 7.5 kmph According to the question, Time = Distance/Speed Hence, Required time = 37.5/12.5 + 37.5/7.5 = 3 + 5 = 8 hours

    Practice Next