Question

three copper cubes whose edges mesure 5cm, 4cm, and 3m respectively are melted to form a single cube. find the surface area of the new cube​

Answer 1

Explanation:

Let x cm be the edge of the new cube.

Then, the volume of the new cube= Sum of the volumes of three cubes

⇒x^3= 5^3+4^3+3^3=216

X^3=6^3 =216 cm

The edge of the new cube is 6cm

Surface area of the new cube= 6a^2 =6(6^2)=216cm^2

Answer 2

${ \huge{ \underline{ \underline{ \sf{ \green{GivEn : }}}}}}$

• Measure of edges of three cubes is 5cm ,4cm and 3cm.

${ \huge{ \underline{ \underline{ \sf{ \green{To \: find :}}}}}}$

• What's the surface area of new cube?

Formula to be used :-

• Volume of cube = s³

Where,

s = measure of side

• Surface area of cube = 6a²

${ \huge{ \underline{ \underline{ \sf{ \green{SoluTion : }}}}}}$

Given that,

Measure of edges of three cubes is 5cm ,4cm and 3cm.

As per question :-

Volume of new cube = Sum of volumes of three cubes.

Now, find the volume of cube.

___________________________________________________

⟶ Volume of cube = s³

⟶ 5³ + 4³ + 3³ = s³

⟶ 125 + 64 + 27 = s³

⟶ 216 = s³

⟶ 6 = s

Hence,

Measure of Side of new cube is 6cm.

_____________________________________________________

Now,find the surface area of new cube.

⟶ Surface area of cube = 6a²

= 6 × 6 × 6

= 216cm²

Hence,

Surface area of new cube = 216cm²