Question

The formula sa

SA
6 gives the length of the side, s, of a cube with a surface area, SA. How much longer is the side
of a cube with a surface area of 180 square meters than a cube with the surface area of 120 square meters?
o
30-45 m
O V30-2V5
o 10 m
215 m

Answer 1

The correct option is (b).

Explanation:

The formula for the side of a cube of surface area SA is as follows :

`s=\sqrt{(SA)/(6)}`

When SA = 180 m²

`s=\sqrt{(180)/(6)}\\\\s=√(30)`

When SA = 120 m²

`s=\sqrt{(120)/(6)}\\\\s=√(20)\\\\=2\sqrt5`

Difference,

`=30-2\sqrt5`

So, the correct option is (b).