Solution of problem N1011 Laplace probability theory

Solution of problem N1011 Laplace probability theory

1011. When hiring candidates, a test is proposed containing 150 questions with three options for each answer, with only one of the answers correct. To successfully pass the test, it is necessary to correctly answer at least 55 questions. What is the probability of getting a job, choosing answers at random?

Additional information:

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