You have been captured by small cute puppy. He has two identical opaque vases, and 100 white beads and 100 black beads. The puppy will allow you to arrange all of the beads in whatever way you like between the two vases, but neither of the vases can be empty. The puppy will then close his eyes, put his little paw into one of the vases, rummage around, and remove just one bead. You have no idea which vase he will choose.
If the puppy chooses a black bead, you will be allowed to stroke his head. But if he chooses a white bead he will bite you. How do you arrange the beads to give yourself the best chance of getting a stroke?
As ever, please do NOT post your answers, but feel free to say if you solved it and how long it took. Solution (and credit for the puzzle) on Monday.