how to find surface area of a  prism
The cross section has the same size and shape as the base, as can be seen in the following diagrams. The surface area of a solid is the total area of all its external faces. To calculate the surface area of a prism we need to: Step 1: Determine the shape of each face. Step 2: Calculate the area of each face. Step 3: Add up all the areas to get the total surface area. We can also use the formula. Surface area of prism = 2 Ã area of base + perimeter of base Ã height. Worksheet to calculate the surface area and volume of a rectangular prism. Example: Calculate the surface area of the following prism. Solution: There are 2 triangles with the base = 4 cm and height = 3 cm.