the blue and green marbles are evenly matched, fifty and fifty
each time a single colored pair is drawn, there is now an "extra" unpaired marble of the other color this extra marble must eventually be drawn along with one of the same color
the number of marbles in the A and B boxes can be anywhere from zero to fifty, but it is the SAME for both boxes
the green and blue marbels in the box are the same one contain fifty and so the other, when u take from one each the number of marbels will increase in same number there both equal.
