### Introduction

In this post we will discuss something is which is very elementary and fascinating, yet not available in a high school curriculum. More precisely we will study a part of solid geometry related to calculation of volume of solids. In so doing we will need the famous*Cavalieri's Principle*which relates volumes of two solids under certain conditions.

### Cavalieri's Principle

The Cavalieri's Principle states that:**If two solids lie between two parallel planes and any plane parallel to these planes intersects both the solids into cross sections of equal areas then the two solids have the same volume.**