Suppose that the pages per book in a library are normally distributed with an unknown mean and standard deviation. The book lengths of39

randomly sampled books are used to estimate the mean of the population. Whatt

-score should be used to find the99%

confidence interval for the population mean?

df

...

36

37

38

39

40

t

0.10

...

1.306

1.305

1.304

1.304

1.303

t

0.05

...

1.688

1.687

1.686

1.685

1.684

t

0.025

...

2.028

2.026

2.024

2.023

2.021

t

0.01

...

2.434

2.431

2.429

2.426

2.423

t

0.005

...

2.719

2.715

2.712

2.708

2.704

Use the portion of the table above or a calculator. If you use a calculator, round your answer to three decimal places.

Provide your answer below: