Thread: volume of Frustum using similar shapes method

what is the volume of frustum of hight 4cm, upper radius of 3cm and a lower radius of 5cm, using similar shapes method.

Question is the frustum part of a cone or a sphere?

Can we solve this using ratios of volumes?

Google

Hi nazz,
1 make a sketch extending the frustrum sides to meet at apex
2 draw the altitude of the cone and id similar triangles. draw the cone diameters
3 set up an equation in which the altitude of the upper cone is x
4 solve for x
5 volume of frustrum equals volume of large cone minus volume of small cone

bjh