Решение задачи N5106 теория вероятностей

5106. There are 15 products in the batch: 10 products of the first grade, and 5 of the second. At random, 3 items are taken one after the other without returning to the lot. Find the probability that at least one item is second grade.

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