Solution of problem N1359 Laplace probability theory

Solution of problem N1359 Laplace probability theory

1359. According to statistics, an average of 87% of newborns survive to 50 years. Find the probability that out of 1,000 newborns, the proportion (frequency) of those who survive to age 50 will: a) be within the range of 0.9 to 0.95; b) will differ from the probability of this event by no more than 0.04 (in absolute value)?

Additional information:

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