Question

three cubes are please adjacently
in a row and the ratio of the total surface area of the new cuboid to the sum of the surface areas of three cubes

Answer 1

Mensuration,

We have,
Three cubes placed side by side in a row.

Have to find the ratio of the new formed cuboid and the sum of the previous cubes.

Let one side of the cube be x units
So the total surface area of a cube will be = 6x²units²

As three cubes are placed adjacently the lenght of the cuboid will be = 3x units
bredth = x units
and height = x units

So the total surface area of the cuboid = 2{(3x×x)+(x×x)+(x×3x)} units²
= 2{(3x²)+(x²)+(3x²)} units²
= 2 × 7x² units²
= 14x²units²

Now the ratio of the total surface of the new formed cuboid and three cubes = 14x²: 3 × 6x²
= 14x²: 24x²
= 7:12

That's it
Hope it helped (･ิω･ิ)