Question
If the height and the radius of the base of a cone are
both doubled, the volume of the cone becomes_____ of its previous volume.Solution
Let's assume the height and the radius of the base of a cone are 'r' and 'h' respectively. Then the volume of cone = (1/3) x ℼ x (r)^2 x h If the height and the radius of the base of a cone are both doubled. New height = 2h New radius = 2r Then the new volume of cone = (1/3) x ℼ x (2r)^2 x 2h = (1/3) x ℼ x 8(r^2) x h So the volume of the cone becomes 8 times of its previous volume.
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