Решение задачи N2904 теория вероятностей

2904. From an urn containing 15 balls, of which 7 are white and 8 are black, 6 balls are removed at random (without returning). Find the probabilities of the following events: A = {all balls drawn are white}; B = {among white balls there are exactly 4 white}.

Detailed solution. Decorated in Microsoft Word 2003 (Quest decided to use the formula editor)