KöMaL 2008 K181
A box contains red, blue and green marbles. At least twelve marbles need to be drawn from the box to make it certain that there will be a red one among them, and at least seventeen need to be drawn to make sure that there is a red one and also a green one among them. At least seven need to be drawn to be certain that there is a marble among them that is not blue. At least how many marbles need to be drawn to make sure that at least two of them are green?
Official text KöMaL. Quoted with source.
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