Question

A poll conducted in 1972 asked 1003 people, " During the past year, about how many books did you read either all or part of the way through?" Results of the survey indicated that x-bar=18.9 books and s=1
9.9 books.

A)Construct a 95% confidence interval for the mean number of books read either all or part of during the preceding year. Interpret the interval.

____,_____

Answer 1

This is the same type of problem as your previous post on confidence intervals.

Use the same formula with these values:

n = 1003
mean = 18.9
sd = 19.9

I'll let you take it from here.

Answer 2

MathGuru, how do i determine the z-score for this one?

Answer 3

95% confidence = 1.96

You can determine these values by using a z-table. Make a note of the more commonly used confidence intervals so you don't have to constantly refer to the table. It will help you remember them too.