The volume of a rectangular parallelepiped (also known as a rectangular prism) is calculated using the formula:
$$V = a \cdot b \cdot c$$
where (a), (b), and (c) are the lengths of its three different sides (length, width, and height). You simply multiply these three dimensions together.
For example, if a rectangular parallelepiped has sides of 3 cm, 4 cm, and 6 cm, then its volume is:
$$V = 3 \cdot 4 \cdot 6 = 72 \text{ cm}^3$$
The volume of a rectangular parallelepiped is equal to the product of its three dimensions.