If the surface area of a cube is 18sq.cm what is the surface area of a cuboid formed by joining 3 of these cubes

in the linear cubiod, three cubes share two faces at each junction, there are two juncions, or 4 surfaces not exposed as surface.

Area of each face joine=18/6 =3cm^2
New surface area=18*3-4*3 cm^2

Area of each face joine =18/6=3cm^2

New surface area =18*3-4*3cm^2 =42

To find the surface area of a cuboid formed by joining 3 of these cubes, we need to know the dimensions of the cuboid.

Let's assume that the side length of each cube is "s" cm. Since the surface area of one cube is given as 18 sq.cm, we can set up the equation:

6s^2 = 18

Dividing both sides by 6, we get:

s^2 = 3

Taking the square root of both sides, we get:

s = √3 cm (side length of each cube)

Now, to find the dimensions of the cuboid formed by joining 3 cubes, we know that the length and width will remain the same as the side length of the cube (s = √3 cm), but the height will be 3 times the side length since we are stacking 3 cubes. Therefore, the dimensions of the cuboid are:

Length = √3 cm
Width = √3 cm
Height = 3 * √3 cm = 3√3 cm

Now, we can calculate the surface area of the cuboid using the formula:

Surface Area = 2(LW + LH + WH)

Substituting the dimensions we found, we get:

Surface Area = 2(√3 * √3 + √3 * 3√3 + √3 * 3√3)
= 2(3 + 3√3 + 9)
= 2(12 + 3√3)
= 24 + 6√3 sq.cm

Therefore, the surface area of the cuboid formed by joining 3 of these cubes is 24 + 6√3 sq.cm.