A solid cone of base radius 10 cm is cut into two parts through the mid-point of its height, by a plane parallel to its base. Find the ratio on the volumes of two parts of the cone.


Given: let the height of the cone be H and its base radius be R


This cone is divided into two parts through the mid-point of the height of the cone such that


ED||BC



Therefore triangle AED is similar to triangle ABC


By the condition of similarity,




Volume of a cone = 1/3 πr2h


Volume of the frustum = Volume of the cone ABC – Volume of the cone AED





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