Two cubes each of volume 64c m 2 are joined end to end find the surface area of the resulting cuboid

Two cubes, each of volume 64 cm3, are joined end to end. Find the total surface area of the resulting cuboid.

Volumebof the cube = a3 

Therefore,

a3 = 64

⇒ a3 = (4)3

⇒ a = 4

Each side of the cube = 4 cm

Then,

length of the cuboid ⇒ (2 × 4)

Breadth of the cuboid = 4 cm

Height of the cuboid = 4 cm

Total surface area of the cuboid = 2(lb+bh+lh)

=2[(8 × 4)+(4 × 4)+(8 × 4)]cm2

=(2 ×  80) cm2 

= 160 cm2 

Concept: Concept of Surface Area, Volume, and Capacity

  Is there an error in this question or solution?

>

2 cubes each of volume 64 cm 3 are joined end to end. Find the surface area of the resulting cuboid in cm 2

Solution

Let l be length of each cube
Volume of each cube = $l^3$ =64 $c{m}^3$

$\Rightarrow$ $l^3=64c{m}^3$

$\Rightarrow$ l = 4 cm
If, we join 2 cubes each having side equal to 4 cm, we get a cuboid

Length of cuboid= L=8 cm

Height of cuboid=H=4 cm

Breadth of cuboid=B=4 cm cm

We know that Surface Area of Cuboid =2(L.B+B.H+H.L)= 2((8x4)+(4x4)+(4x8))

=2(32+16+32)

= 2(80)

=160 $c{m}^2$