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

    Question

    Speed of a boat in still water is 4 times more than the

    speed of stream. If boat covers 120 km in downstream in 8 hours, then find the time taken by the boat to cover 108 km in upstream.
    A 12 hours Correct Answer Incorrect Answer
    B 11 hours Correct Answer Incorrect Answer
    C 8 hours Correct Answer Incorrect Answer
    D 9 hours Correct Answer Incorrect Answer

    Solution

    Let the speed of stream be ‘x’ km/hr. So, speed of boat in still water = 4 × x = 4x km/hr Downstream speed of boat = 4x + x = 5x km/hr According to question; 5x = 120/8 = 15 Or, x = 3 Upstream speed of the boat = 4x – x = 3x = 3 × 3 = 9 km/hr Required time taken = 108/9 = 12 hours

    Practice Next

    Relevant for Exams: