Question

A survey was conducted that asked 1015 people how many books they had read in the past year. Results indicated that x overbar equals14.5 books and sequals 16.6 books. Construct a 95 ​% confidence interval for the mean number of books people read. Interpret the interval.

A.There is 95​%confidence that the population mean number of books read is between and .

.

B.There is a 95% chance that the true mean number of books read is between   and .

.

C. If repeated samples are​ taken, 95​% of them will have a sample mean between and .

.

Answer 1

(a)

SE=s/

= 16.6/ = 0.5210

= 0.05

ndf = n - 1 = 1015 - 1 = 1014

From Table, critical values of = 1.9623

Confidence Interval:

14.5 (1.9623 X 0.5210)

= 14.5 1.0224

= ( 13.4776, 15.5224)

Confidence Interval:

13.4776 < < 15.5224

(b)

Correct option:

B. There is 95% chance that the true mean number of books read is between 13.4776 and 15.5224.