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

    Question

    A boat can travel 42 km downstream in 60 min. The ratio

    of the speed of the boat in still water to the speed of the stream is 5: 2. How much time will the boat take to cover 21 km upstream?
    A 1 hour 12 min Correct Answer Incorrect Answer
    B 1 hour 10 min Correct Answer Incorrect Answer
    C 1 hour 50 min Correct Answer Incorrect Answer
    D 2 hour 30 min Correct Answer Incorrect Answer

    Solution

    Speed of downstream = D/T = 42 × (60/60) = 42 km/hr The ratio of the speed of the boat in still water to the speed of the stream = 5: 2 (5x, 2x) => 7x = 42 => x = 6 Speed of upstream = 5x – 2x = 3x = 18 km/hr Distance = 21 km Time = D/S = 21/18 = 1(1/6) hr = 1 hour 10 min

    Practice Next

    Relevant for Exams: