New RBI Grade B 2025 Notification will come Soon! Enroll Here

    Question

    ST

    A motor-cycle covers 140 km with a speed of 40 km/hr.

    find the speed of the motor-cycle for the next 140 km journey so that the average speed of the whole journey will be 55 km/hr.
    A 117 km/hr Correct Answer Incorrect Answer
    B 150 km/hr Correct Answer Incorrect Answer
    C 120 km/hr Correct Answer Incorrect Answer
    D 88 km/hr Correct Answer Incorrect Answer
    E 90 km/hr Correct Answer Incorrect Answer

    Solution

    Average speed of whole journey = 55 km/hr Using the formula, average speed = 2xy/(x + y) rArr; x = speed of first 140 km = 40 km/hr rArr; 55 = 2 times; (40 times; y)/(40 + y) rArr; 88 km/hr

    Practice Next

    Relevant for Exams: