Hi! I was researching about math games to have some inspiration for a College project, and i loved your game so much!!! i liked your ideia, it's kinda of simple but it's so fun and so useful at the same time.
I saw some 'bugs' in your game, like, at level 7 i was able to sum infinity -infinity (LMAO i was having fun doing), and at level 7 again, my x = 0.4 and my y = 0.3, the sum was supposed to be 0.7, right? yeah, but I didn't win. i will post the picture right bellow to you see.
but in general your game is amazing!
so... thanks for the game, dude. i hope more levels. see ya! (sorry about my english, i'm not a native speaker LOL)