Question

four cubes of side 7 cm are joined together to form a cuboid find the surface area of the resulting cuboid​

Answer 1

Given,

Side of a cube = 7cm

When they joined together the length of the four cube = 7 × 4 = 28cm

Then the length of the cuboid= 28cm

In a cube the height and the side is same.

Hence, the height of the cuboid = 7cm

breadth is also = 7cm

TSA of a cuboid :

= 2(l × b + b × h + h × l )

= 2( 28 × 7 + 7 × 7 + 7 × 28 )

= 2( 196 + 49 + 196 )

= 2( 392 + 49 )

= 2 ( 441)

= 882 cm^2

Therefore, the surface area of cuboid = 882cm^2

Answer 2

$\huge \bold \pink{heya \: mate}$

Length of each side of the cube=7 cm

Now, 4 cubes are joined end to end,

Therefore,

length of the cube,l=7+7+7+7=28 cm

Breadth, b=7 cm

Height, h=7 cm

Surface area of the resulting cuboid=2(lb+bh+hl)

=2(28×7+7×7+7×28) cm²

=2(196+49+196) cm²

=2(441) cm²

=882 cm²