Question

The surface area of one cube is twice the surface area of a second cube.

What is the ratio of the lengths of their edges?

Answer 1

8:1

Explanation:

Volume of a cube = Length of edge³

So the equation for the small cube is,

V=L³

If the edge of the bigger cube is twice as long as the smaller cubes edge, then the equation for the bigger cube is:

V = (2L)³

= (2³)L³

= (8)L³

Combining these two in ratio form:

(8)L³ : (1)L³

You can remove the L³ from each side because they are equal

So the answer is 8:1

Answer 2

The ratio is square root of 2.