Question

The surface areas of two cubes have a ratio of 49 to 81. What is the

ratio of the edge lengths of the two cubes?

A

7 to 9

B

1 to 32

C

32 to 49

D

3 to 4

Answer 1

A

7 to 9

Explanation:

We have that:

The ratio of the edges is x.

The ratio of the surface areas is given by
`x^2`

The ratio of the volumes is given by
`x^3`

In this question, we have that:

`x^2 = (49)/(81)`

So

`x = \sqrt{(49)/(81)} = (7)/(9)`

So the correct answer is given by option A.