Question

    The speed of boat downstream and upstream is 28 km/hr and 18 km/hr respectively. Time taken to travel a distance of (m + 35) km downstream and (n + 22) km upstream is 11 hours, and time taken to travel (m + 85) km upstream and (n + 65) km downstream is 17 hours. Find the difference between the value of m and value of n.

    A 25 Correct Answer Incorrect Answer
    B 10 Correct Answer Incorrect Answer
    C 20 Correct Answer Incorrect Answer
    D 15 Correct Answer Incorrect Answer
    E None of these Correct Answer Incorrect Answer

    Solution

    According to question, (m+35)/28+(n+22)/18=11 (2m+70+3n+66)/56=11 2m+3n=616–136=480 … (iii) Also, (m+85)/18+(n+65)/28=17 (3m+255+2n+130)/56=17 3m+2n=952–385=567 … (iv) Solving equation (iii) and (iv), we get, m=105 and n=95 Therefore, required difference = 105 – 95 = 10

    Practice Next