Решение задачи N1865 теория вероятностей

1865. The probability of correct registration of the account at the enterprise in the first department is 0.95 for the second and the third 0.8 and 0.9, respectively. During the audit, three accounts were taken (one from each department). Find the probability that they are correctly drawn up a) all three accounts b) only two accounts.

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