Question

Three metal cubes with edges 15 Cm, 12 cm , and 9 cm. respectively are melted together and formed into a simple cube. Find the diagonal of this cube.​

Answer 1

Step-by-step explanation:

find the volume of the 3 cubes and add them to get the volume of the big cube, then cube root it to find it's edge,

a cube is a 3D square,

now look it as 2D, its a square with side equal to the edge of the big cube, now find its diagonal

Answer 2

Given:-

Edge of 3 cubes.

• edge of cube 1 = 15cm.
• edge of cube 2 = 12cm.
• edge of cube 3 = 9cm.

Concept:-

• sum of the Volumes of the 3 cubes = volume of the new cube.

Solution:-

Volume of a cube = a³

hence, 15³+12³+9³ = a³

3375 + 1728 + 729 = a³

5832 = a³

a = 18 cm.

Diagonal of a cube = √3a

= 18√3 cm.