Page 1 - LN-Surface Area
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SAI International School
                                                       CLASS - VIII


                  Mathematics
                  CHAPTER-11 :Mensuration                                       Lesson Notes-3


                  SUBTOPICS: Suface area of solid shapes


                  Solid Shapes

                  Many objects that we see in our day to day life like book, pencil box, ice cream cone,
                  football and cylinder are three-dimensional objects (solid shapes). All these objects
                  occupy some shape and have three dimensions- length, breadth and height or
                  depth. Some shapes have two or more than two identical (congruent) faces. For
                  example the cylinder has congruent circular faces that are parallel to each other.

                  Surface area of Cube, Cuboids and Cylinder


                  The surface area of a solid is the sum of the areas of its faces.

                  Cube:
                  If each side of the cube is a, then total surface area = 6a 2























                  Lateral surface area of cube: 4a 2

                  Cuboid:
                  Let h, l and b are the height, length and width of the cuboid respectively.

                  So, total surface area = 2 (h * l + b * h + b * l) = 2(lb + bh + hl)










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