Question

    A man can row at 15 km/hr in still water. If the

    velocity of current is 3 km/hr and it takes him 1 hour to row to a place and come back, how far is the place?
    A 7.2 km Correct Answer Incorrect Answer
    B 4.8 km Correct Answer Incorrect Answer
    C 9.6 km Correct Answer Incorrect Answer
    D 2.1 km Correct Answer Incorrect Answer
    E 3.75 km Correct Answer Incorrect Answer

    Solution

    Let the distance be x km. Speed upstream = 15 – 3 = 12 km/hr Speed downstream = 15 + 3 = 18 km/hr ⇒ x/12 + x/18 = 1 ⇒ (3x + 2x)/36 = 1 ⇒ 5x = 36 ⇒ x = 36/5 = 7.2 km

    Practice Next