Question: Millions of Americans arrange travel plans on the WEB. A recent survey reported that 77% purchase plane tickets on the Web. Suppose the survey was based on 1,000 respondents:

A) Construct a 95% Confidence Interval estimate for the population proportion of Americans who purchase plane tickets on the Web.

B) Construct a 90% Confidence Interval estimate for the population proportion of Americans who purchase plane tickets on the Web.

For this problem the book gives a- 0.74≤≤0.80 and b- 0.75≤≤0.79