Solution of problem N1079 Laplace probability theory

Solution of problem N1079 Laplace probability theory

1079. The probability of obtaining a product of the first grade from the conveyor is 0.9. Determine the likelihood that of 500 items taken for inspection:
(a) 460 will be of the first kind;
b) from 400 to 480 (inclusive) will be the first grade.
Find the most probable number of first-class products among 500 items.

Additional information:

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