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In: Statistics and Probability

A publisher wants to estimate the mean length of time​ (in minutes) all adults spend reading...

A publisher wants to estimate the mean length of time​ (in minutes) all adults spend reading newspapers. To determine this​ estimate, the publisher takes a random sample of 15 people and obtains the results below. From past​ studies, the publisher assumes σ is 2.1 minutes and that the population of times is normally distributed.

10 12 7 10 11 8 12 8 11 7 6 11 8 8 12

a) The​ 90% confidence interval is ​____

b) The​ 99% confidence interval is ____

c) Which interval is​ wider?

  1. The​ 99% confidence interval

  2. The​ 90% confidence interval

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Expert Solution

orchestra answered 2 years ago
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