Solution of problem N4166 Laplace probability theory

Solution of problem N4166 Laplace probability theory

4166. The probability of occurrence of event A in a single trial is 0.8
a. Find the probability that A will occur 330 times in a series of 400 tests;
b. Find the probability that A comes from 280 to 300 times in a series of 360 tests.

Additional information:

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