📢 Too many exams? Don’t know which one suits you best? Book Your Free Expert 👉 call Now!
  • google app store apple app store
    • ✖

      Question

      When travelling with the current, a man takes 4 hours

      to cover the distance that he would've covered in 12 hours while travelling against the current. If the current flows at 10 km/h, then find the time taken by the boat to cover 10 km in still water.
      A 20 minutes Correct Answer Incorrect Answer
      B 45 minutes Correct Answer Incorrect Answer
      C 30 minutes Correct Answer Incorrect Answer
      D 40 minutes Correct Answer Incorrect Answer
      E 15 minutes Correct Answer Incorrect Answer

      Solution

      Let the speed of the boat in still water be 'x' km/hr Therefore, distance covered in upstream = 12 X (x - 10) km Also, distance covered in downstream = 4 X (x + 10) km According to the question, 12 X (x - 10) = 4 X (x + 10) Or, {(x + 10)/(x - 10)} = (12/4) = (3/1) Or, x + 10 = 3x - 30 Or, 2x = 40 => 'x' = 20 So, speed of the boat in still water = 20 km/h So, required time = (10/20) X 60 = 30 minutes

      Practice Next
      More Boats and streams Questions

      Relevant for Exams:

      ask-question