Решение задачи N4545 теория вероятностей

4545. The urn contains 8 white, 8 red and 4 blue. Find the probability that
a) the ball chosen at random turns out to be white;
b) two balls taken out at random will turn out to be blue;
c) the ball taken out at random turns out to be colored.

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