A very simple question on Cube root

I think it's safe to say that the GMAT will not require you to find the cube root of a value, unless the cube root turns out to be an integer.
So, for example, you should know that the cube root of 8 is 2, and the cube root of 125 is 5

On the GMAT, if the cube root of some number is not an integer, then you'd most likely need to determine which range of values works.

For example:
The cube root of 24 is
(A) Between 0 and 1
(B) Between 1 and 2
(C) Between 2 and 3
(D) Between 3 and 4
(E) Between 4 and 5

Solution: since the cube root of 8 equals 2, and the cube root of 27 equals 3, we can conclude that the cube root of 24 lies between 2 and 3. So, the answer is C

So, if we return to your original question (the cube root of 4), we can see that, since the cube root of 1 equals 1, and the cube root of 8 equals 2, then the cube root of 4 lies between 1 and 2.
In other words, the cube root of 4 = 1.something

This is probably as deep as we need to go for the GMAT

Cheers,
Brent