Math New Drill (Level 1) : Geometry (Solid figure) Problem1(7) JOSAIKAWAGOE-2014

Find the volume of the solid which is made by the rotation of the figure below around the line AB as a rotation axis.
Pi is assumed to be 3.14.

Answer

1554.3 cm³

Solution

This figure is divided into two part of M and N as shown in the figure below. 

The volume of M + N is 7 × 7 × 3.14 × 5 + 5 × 5 × 3.15 × 10 = 495 × 3.14 = 1554.3 cm³.