ЁЯУв Too many exams? DonтАЩt know which one suits you best? Book Your Free Expert ЁЯСЙ call Now!

    тЪб Month End Offer - Flat 52% Off On All Courses! Enroll Now тЪб
    00:00:00 AM Left

    Question

    A submarine can navigate 112 km upstream and 130 km

    downstream, and it takes a total of 8 hours and 6 minutes to complete this journey. Now, the task is to calculate the time required for the submarine to travel 64 km upstream and 195 km downstream, taking into account that the ratio of the submarine's speed in still water to the speed of the stream is 9:4.
    A 6 hrs 45 min Correct Answer Incorrect Answer
    B 2 hrs 57 min Correct Answer Incorrect Answer
    C 6 hrs 57 min Correct Answer Incorrect Answer
    D 8 hrs 57 min Correct Answer Incorrect Answer
    E none of these Correct Answer Incorrect Answer

    Solution

    ATQ, Let, speed of Submarine in still water and speed of stream is тАШ9aтАЩ km/h and тАШ4aтАЩ km/h, respectively. Upstream speed = 9a тАУ 4a = 5a km/h Downstream speed = 9a + 4a = 13a km/h So, 112/5a + 130/13a = 81/10 Or, (22.4 + 10) ├Ч 10/81 = a Or, a = 4 Upstream speed = 5 ├Ч 4 = 20 km/h Downstream speed = 13 ├Ч 4 = 52 km/h Desired time = (64/20) + (195/52) = 3.2 + 3.75 = 6 hrs 57 minutes

    Practice Next
    More Boats and streams Questions
    ask-question