A cubical box has each edge 10 cm and another cuboidal box is 12.5 cm long, 10 cm wide and 8 cm high. (i) Which box has the greater lateral surface area and by how much? (ii) Which box has the smaller total surface area and by how much?
Answers
has each edge 10 cm and another cuboidal box is 12.5 cm long, 10 cm wide and 8 cm high. (i) Which box has the greater lateral surface area and by how much? (ii) Which box has the smaller total surface area and by how much
Answer:
The cube with an edge length of 10cm has a greater lateral surface area of 400. The cuboid only has an area of 360
The cuboid however has a greater total surface area with 610 while the cube only has 600.
Step-by-step explanation:
The lateral surface area of any 3-D shape is the area of the walls excluding the top and the bottom.
For a cube, that would be 4 because is the area of any one surface area of the cube.
For a cuboid, that would be 2(lxh)+2(bxh). (Draw a cuboid shape on a piece of paper to understand this better).
By this formula, the cube's LSA comes out to be . This equals to 4(100) and thus 400.
Cuboid's LSA comes out to be 2(12.5x8)+2(10x8). This equals 2(100)+2(80)=200+160=360.
The total surface area of any 3-D shape is area of all walls including the top and the bottom.
For a cube, this would be 6. Thus, 6(100) which is 600.
For a cuboid, that would be 2[(lxb)+(bxh)+(hxl)]. This gives us 2(100+80+125)=610