The document provides a formula for calculating the total surface area of a rectangular prism. The surface area equals 2 times the sum of the length times breadth, length times height, and breadth times height. This gives the total area of all 6 faces/rectangles of the prism as the sum of their individual areas.

7. 5
h
1
h
2 2
h
3
6
h
4

9. •The total surface area of a rectangular prism
= Area of 6 rectangles
=lb+bh+lh+bh+lh
=2lb+2lh+2bh
=2(lb+bh+lh)

10. Total surface area of a Rectangular prism
Total surface area of a Rectangular prism
=2(lb+bh=lh)
i– length of the rectangular prism
b-breadth of the rectangular prism
h – height of rectangular prism