1337. The probability that the part is standard is p = 0.9. To find:
a) with a probability of 0.9545 boundaries (symmetric with respect to p), in which a fraction of the standard among the checked 900 parts is enclosed;
b) the probability that the share of non-standard parts among them is in the range from 0.08 to 0.11.

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