If you want to divide the material evenly, you can make it easier to divide the material by intentionally setting the scale to a value that is easy to divide.
For example, if you divide it into three, it may not be divisible by a number. In such cases, it is recommended to place the square in a position that can be read in multiples of 3.
You can get accurate dimensions with a little ingenuity.

How to divide the material using a square