Question

Two cubes each of length of edge b units ,are joined end to end .Find the total surface area of cube.

Answer 1

The total surface area of the cuboid is 10b² sq. units.

• Two cubes have length equal to b units.

• Both of them are joined together by one side.

• Therefore, one dimension of the cube gets increased by b units.

• Therefore, the dimensions of the so formed cube is equal to b, 2b, b units.

• Now, the surface area of the cuboid is

Surface area = 2 (lb + bh + hl)

Surface area = 2 (2b² + 2b² + b²)

Surface area = 10b² sq. units

• Surface area of the cuboid is 10b² sq. units.