Question 1: Webster Library wants to know how many green books it has. Out of the 500 shelves of books, 3 shelves were selected. These shelves hold 150 books each. 54 of the books sampled were green.
Part 1: What percentage of the books is green?
Part 2: What is the 90% confidence interval for the percentage of green books?
Part 3: How many books need to be sampled to be within 4% with 95% confidence?
Question 2: 35 books were sampled at the bookstore. They had an average price of $160 with a standard deviation of $43.
Part 1: What is the 95% confidence interval for the average price of a book?
Part 2: How many books need to be checked to be 90% confident that the average price was within $10?
Solve these questions in details and provide examples to support your rationale.