Question 27
Vangelis has a box containing $2015$ white and $2015$ black balls. He follows the following procedure: He chooses randomly two balls from the box. If both are black, then paints one of them white and puts it in the box, while drops the other out of the box. If both are white, then he keeps one of them in the box and drops the other out of the box. If one ball is white and the other is black, then he keeps the black in the box and drops out the white ball. He follows the procedure, until only $3$ balls remain in the box. Then he realizes that in the box exist balls of both colors.
Determine how many white and how many black balls exist finally in the box.
Determine how many white and how many black balls exist finally in the box.