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

    Question

    If the radius of a right circular cylinder is doubled

    (an increase of 100%), and its height is reduced by half (a decrease of 50%), what will be the ratio of the volume of the original cylinder to the volume of the modified cylinder?
    A 1:4 Correct Answer Incorrect Answer
    B 4:1 Correct Answer Incorrect Answer
    C 1:2 Correct Answer Incorrect Answer
    D 2:10 Correct Answer Incorrect Answer

    Solution

    Let the radius and height of the old cylinder be 'r' units and 'h' units, respectively Volume of the old cylinder = π X r2 X h = πr2h cubic units Radius of the new cylinder = r X 2 = '2r' units Height of the new cylinder = h X 0.5 = '0.5h' units So, volume of the new cylinder = π X (2r)2 X 0.5h = 2πr2h cubic units So, required ratio = πr2h:2πr2h = 1:2

    Practice Next

    Relevant for Exams: