# Cube Edge Ratio

A cube has a volume of 128 cubic cm. It is divided into 8 equal cubes. Find the ratio of edge of smaller cube to the edge of original cube

#### ELLEN MELLO

• Apr 18th, 2017

It is not a cube. Because if ti is a cube then the volume should be a possible cube of a number

#### Utkarsh Sharma

• Jul 8th, 2017

Going by the values provided the answer is approximately 0.5,
a^3=128
a=5.03 cm-------eq 1
Now, if the bigger cube is divided into 8 cubes then those 8 cubes will have same volume and the total of that would account to 128 cm^3.
Therefore for the smaller cube we will find the edge as:
a^3=128/8,
a=2.51 cm ----- eq2.
Finally eq 2/eq 1 ~= 0.499 or 0.5

#### Muralidharan

• Aug 19th, 2017

1 : 2
side of the large cube = 128 ^ (1/3) = 4 * [2^(1/3)]
volume of the small cube = 128 / 8 = 16
side of the small cube = 16 ^ (1/3) = 2 * [2^(1/3)]
Ratio of the edge of the small cube to that of the large cube = 2 * [2^(1/3)] : 4 * [2^(1/3)] = 1 : 2

#### SAMEER KUMAR

• Aug 20th, 2017

vol of large cube = 128
vol of smaller cube = 128/8
ratio of vol = 128/8 : 128 = 1:8
ratio of size = (1:8)^(1/3) = 1:2  