The easy level is just way too easy, like, all you have to do is keep it between 0 and 20 and that's it.
But that hard mode becomes really hard really soon(after the dividing comes into play), so difficult i gave up after a few minutes. There are just simply too many possibilities that can be considered to be able to actually do it in your head or even with a piece of paper.
Before that it was kinda fun. BUT i think it should be possible for the player to move around the chips on the board, so that he can reorganize them to his own liking. It would make it more enjoyable.