Let the radius and height of the cylinder be r cm and h cm respectively. Volume of the cylinder = πr2h New radius of the cylinder = r × (1/3) = r/3 Let the new height of the cylinder be H cm then According to the question π (r/3)2H=πr2h ⇒(r2/9) × H = r2h ⇒ H = 9h So, the height becomes 9 times of the initial height.