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

    Question

    The downstream and upstream speeds of a boat are 36 km/hr

    and 28 km/hr, respectively. If the boatman covers (x + y) km upstream in 8 hours while the stream flows at double its usual speed, find the average of x and y.
    A 96 km Correct Answer Incorrect Answer
    B 60 km Correct Answer Incorrect Answer
    C 73 km Correct Answer Incorrect Answer
    D 85 km Correct Answer Incorrect Answer
    E None of these Correct Answer Incorrect Answer

    Solution

    ATQ,

    Let, speed of boat in still water and stream speed be B km/hour and s km/hour, respectively.

    So, (B + s) = 36 тАж (i)

    Also, (B тАУ s) = 28 тАж (ii)

    Solving equation (i), and (ii), we get,

    B = 32 km/hour

    s = 4 km/hour

    According to question,

    (x + y)/(B тАУ 2s) = 8

    (x + y) = 8 ├Ч (32 тАУ 2 ├Ч 4) = 8 ├Ч 24 = 192 km

    Therefore, average value of x and y = (x + y)/2 = 192/2 = 96 km

    Practice Next
    More Boats and streams Questions

    Relevant for Exams:

    ask-question