Question

    A person travels at the speed of 16kmph, 24kmph and

    12kmph on the surface of an equilateral triangle and the ground. Find the average speed of the entire journey. (In Kmph)
    A 16 Correct Answer Incorrect Answer
    B 17 Correct Answer Incorrect Answer
    C 15 Correct Answer Incorrect Answer
    D 18 Correct Answer Incorrect Answer

    Solution

    Let the side of the triangle be 72 km. As we know, Average speed = total distance/total time Time to cover 72 km distance with the speed of 16 km/hr = 72/16 = 4.5 hrs Time to cover 72 km distance whit the speed of 24 km/hr = 72/24 = 3 hrs Time to cover 72 km distance with the speed of 12 km/hr = 72/12 = 6 hrs   Average speed = (3 x 72) / (4.5+ 3+6) = 216/13.5 = 16 km/hr

    Practice Next