Question

Two cubes each of ‘a’ cm edge are joined end to end. Find the surface area of the resulting cuboid.

Answer 1

Given, the edge of the cube is a cm.

When two cubes are joined end to end, then the resulting solid is a cuboid.

Length of the cuboid, l = 2 × Edge of the cube = 2 × acm = 2a cm

Breadth of the cuboid, b = Edge of the cube = acm

Height of the cuboid, h = Edge of the cube = a cm

Surface area of the cuboid

= 2 (lb + bh + hl)

= 2 (2a cm × a cm + a c × a cm + a cm × 2a cm)

= 2 (2a^2+a^2+2a^2)

= 2 × 5a2

= 10a2

Thus, the surface area of the resulting cuboid is 10a^2 cm2.