Question

three cubes of volume 343 cm ³ are joined end to end . Find the surface area of the resulting cuboid and volume ​

Answer 1

Answer:

Volume of cube = x³

➟ 343cm³ = x³

➟\sf \sqrt[3]{343} = x➟

3

343

=x

➯ 7cm = x

Hence, side of a cube is 7cm

when two cubes are joined side by side,

Then,

Length = (7 + 7) = 14cm

Breadth = 7cm

Height = 7cm

Volume of cuboid = lbh

➟ (14 × 7 × 7)cm³

➯ 686cm³

Hence, The volume of a cuboid is 686cm³

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

➟ 2(14 × 7 + 7 × 7 + 7 × 14)cm²

➟ 2(98 + 49 + 98)cm²

➟ 2(245)cm²

➯ 490cm²

Hence, The surface area of cuboid is 490cm²

Answer 2

Answer :

• Volume of cuboid = 1029cm^3
• Surface area of cuboid = 686cm^2

Exᴘʟᴀɪɴᴀᴛɪᴏɴ ⇩

Given,

• volume of cube = 343cm^3

To find ,

• Volume of cuboid
• surface area of cuboid

To find Volume and surface area we need side

• Let side be 'a'

Here ,

⇛ Volume of cube = a³

⇛ 343 = a³

⇛ a = 7cm

There are three cubes so ( 7 × 3 = 21cm)

⇛ Length = 21cm

⇛ breadth = 7cm

⇛ Height = 7cm

Now ,

⇛ Volume of cuboid = l × b × h

= 21 × 7 × 7

= 1029cm^3

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

= 2 ( 21 × 7 + 7 × 7 + 7× 21

= 2 × 343

= 686cm^2