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

    Question

    Speed of a boat in still water to speed of boat in

    upstream is 7: 6. If the boat can travel 320 km in downstream in 4 hours, then find the time taken by the boat to cover 21 km in still water.
    A 30 minutes Correct Answer Incorrect Answer
    B 15 minutes Correct Answer Incorrect Answer
    C 10 minutes Correct Answer Incorrect Answer
    D 18 minutes Correct Answer Incorrect Answer

    Solution

    Let speed of boat in still water and speed of boat in upstream be тАШ7xтАЩ km/h and тАШ6xтАЩ km/h, respectively. Speed of stream = 7x тАУ 6x = x km/h Speed of boat in downstream = 7x + x = 8x km/h So, 8x = 320/4 => x = 10 Speed of boat in still water = 7 ├Ч 10 = 70 km/h Desired time = 21/70 x 60 = 18 minutes

    Practice Next
    More Boats and streams Questions

    Relevant for Exams:

    ask-question