Question

Two cubes each of volume 64cm^3 are joined end-to-end. find the surface area and volume of resulting cuboid.

Answer 1

Volume of cube =64cm³
So side of cube =³√64 cm =4 cm
When cubes are joined length of new cuboid =4+4=8cm
Breadth =4cm
Height=4 cm
Surface area =2lb+2bh+2lh
=2x8x4+2x4x4+2x4x8
=64+32+64
=160cm²
Volume =lbh=4x4x8=128 cm³

Answer 2

Hello......... ^_^

Here is your answer.....

Given :- Two cubes of each volume is 64cm cube.

$first \: \: cube \: \: volume \: = 64 {cm}^{3} \\ \\ first \: \: cube \: = {(side)}^{3} = 64 {cm}^{3} \\ \\ first \: \: cube \: = side = \sqrt[3]{64} \\ \\ first \: \: cube \: = side \: = 4cm$
as second cube was having same volume as first cube so, it's side is also 4cm.

(According to the question)
the two cubes are joined end to end.

so, the form a cuboid
cuboid length (l) = 4 + 4 = 8cm
breadth (b) = 4 cm
height (h) = 4 cm

$Total \: \: surface \: \: area \: \: of \: \: cuboid = 2( lb + bh + hl ) \: {cm}^{2} \\ \\ = 2 ( 8 \times 4 + 4 \times 4 + 4 \times 8 ) {cm}^{2} \\ \\ = 2 ( 32 + 16 + 32 ) {cm}^{2} \\ \\ = 2 ( 80 ) {cm}^{2} \\ \\ = 2 \times 80 {cm}^{2} \\ \\ = 160 \: {cm}^{2}$
Hence, Total surface area of cuboid (formed by joining two cubes) = 160 cm square.



Hope it helps........... ^_^