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

Answer:

The correct option is (b).

Step-by-step explanation:

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

$s=\sqrt{\dfrac{SA}{6}}$

When SA = 180 m²

$s=\sqrt{\dfrac{180}{6}}\\\\s=\sqrt{30}$

When SA = 120 m²

$s=\sqrt{\dfrac{120}{6}}\\\\s=\sqrt{20}\\\\=2\sqrt5$

Difference,

$=30-2\sqrt5$

So, the correct option is (b).