When two cube of side 12 cm are joined end to end to form a cuboid then the total surface area of cuboid is

total surface area of one cube of side 12 = 6(12^2) = 864

when joined , two faces will not be seen

total surface area = 2(864) - 2(12^2) = 1440

-3cm*4cm*scm

To find the total surface area of the cuboid formed by joining two cubes, we need to determine the dimensions of the cuboid.

When two cubes of side 12 cm are joined end to end, it means that the length of the cuboid will be equal to the sum of the side lengths of the two cubes.

Therefore, the length of the cuboid = 12 cm + 12 cm = 24 cm.

The width and height of the cuboid will be equal to the side length of the cubes, which is 12 cm.

Now, let's calculate the total surface area of the cuboid.

The total surface area of a cuboid can be calculated using the formula:

Total Surface Area = 2lw + 2lh + 2wh

where l, w, and h represent the length, width, and height respectively.

Substituting the values into the formula:

Total Surface Area = 2(24 cm)(12 cm) + 2(24 cm)(12 cm) + 2(12 cm)(12 cm)

Total Surface Area = 576 cm² + 576 cm² + 288 cm²

Total Surface Area = 1440 cm²

Therefore, the total surface area of the cuboid formed by joining two cubes of side 12 cm each is 1440 square centimeters.