Question

A survey was conducted that asked 1002 people how many books they had read in the past year. Results indicated that x = 10.7 books and s = 16.6 books. Construct a 99% confidence interval for the mean number of books people read. Interpret the interval.

Construct a 99% confidence interval for the mean number of books people read and interpret the result. Select the correct choice below and fill in the answer boxes to your choice.complete.
There is a 99% chance that the true mean number of books read is between__and__

Answer 1

A 99% confidence interval for the mean number of books people read is:

CI = (9.35, 12.05)

How to find the confidence Interval?

The formula for confidence interval is:

CI = x' ± z(s/√n)

where:

x' is sample mean

z is z-score at confidence level

s is standard deviation

n is sample size

At 99% confidence level, we have:

z = 2.58

Thus:

CI = 10.7 ± 2.58(16.6/√1002)

CI = (9.35, 12.05)