Question

four cubes each of side 3cm are joined to form a cuboid calculate the surface area

Answer 1

Hi friend,
when four cubes 3 cm each joined to form a cuboid then the dimensions of the cuboid formed are length = 3cm, breadth = 3cm  and height = 12 cm
TSA of cuboid= 2(lb+bh+hl)
                      = 2(3x3+12x3+12x3)
                      =2(9+36+36)
                      =2(81)
                      =162 cm²
____________________________________________________Thanks :)_

Answer 2

as the cubes are joined now,
the length of the new cuboid is 4 *3= 12cm
the height and breadth remain same =3
so,
l=12
b=3
h=3

surface area of a cuboid=2 (lb+bh+hl)
=2(12x3 + 3x3 +12x3)
=2(36 +9+36)
=2(81)
=162 cm^2
thus the surface area of the resulting cuboid =162cm ^2

hope it helps!!!!