Given,

The dimensions of a metallic cuboid = 100 cm × 80 cm × 64 cm

Let’s find out the volume of the cuboid first;

Volume of the cuboid = l × b × h

⇒ 100 × 80 × 64 = 512000cm³

As cuboid is recast into a cube;

So,

Volume of cube = volume of cuboid

⇒ l³ = 512000 ⇒ l =

⇒ l = 80 cm

Now,

As the length of the side of the cube = 80 cm

The surface area of the cube = 6(l)²

= 6 x 80 x 80

= 38400 cm²

So, the surface area of the cube is 38400 cm²