New RBI Grade B 2025 Notification will come Soon! Enroll Here

    Question

    A boat can travel 16 km more in downstream than that in

    upstream, in 8 hours while the difference between the time taken by the same boat to travel 150 km and 130 km, in still water, is 4 hours. Find the approximate time taken by the boat to travel 250 km in downstream and 199 km in upstream.
    A 52 hours Correct Answer Incorrect Answer
    B 82 hours Correct Answer Incorrect Answer
    C 92 hours Correct Answer Incorrect Answer
    D 62 hours Correct Answer Incorrect Answer
    E None of these Correct Answer Incorrect Answer

    Solution

    Let the speed of boat in still water and speed of stream be 'x' km/hr and 'y' km/hr, respectively. According to question; (150/x) - (130/x) = 4 Or, (20/x) = 4 So, x = 5 Now, 8 x (5 + y) = 8 x (5 - y) + 16 Or, 40 + 8y = 40 - 8y + 16 Or,  16y = 16 So, y = 1 So, downstream speed of the boat = (5 + 1) = 6 km/hr And, upstream speed of the boat = (5 - 1) = 4 km/hr Required time taken = (250/6) + (190/4) ~ (42 + 50) ~ 92 hours

    Practice Next