Consider the right prism as shown in the figure below. There are as many cubic units in each layer parallel to the base as there are square units in the area of the base. Also, there are as many layers of cubic units in the prism as there are linear units in the altitudes . We can, therefore, find the total number of cubic units in the prism by multiplying the area of the base by the altitude.
Volume of the prism Area of the base Height of the prism
Rule: The volume of the prism equals its base times its altitude.
The base of a right prism is an equilateral triangle with a side of cm and its height is cm. Find its volume.
Since the base is an equilateral triangle:
The sides of a triangular prism are cm, cm and cm respectively. The volume of the prism is cubic cm. What is its height?