Question

A company that produces cell phones claims its standard phone battery lasts longer on average than other batteries in the market. To support this​ claim, the company publishes an ad reporting the results of a recent experiment showing that under normal​ usage, their batteries last at least 35 hours. To investigate this​ claim, a consumer advocacy group asked the company for the raw​ data, which are shown to the right. Find a 95 ​% confidence interval and state your conclusion. Explain how you dealt with any outliers. 31 35 30 33 34 31 32 31 34 56 32 31 Find a 95 ​% confidence interval for the true mean. What do you conclude about the​ claim? If there are​ outliers, find intervals with and without the outliers present. Find the confidence interval using all of the data. The confidence interval is left parenthesis nothing comma nothing right parenthesis . ​(Round to two decimal places as​ needed.) If outliers are​ present, find the confidence interval without the outliers. Select the correct choice below​ and, if​ necessary, fill in the answer boxes within your choice. A. The confidence interval is left parenthesis nothing comma nothing right parenthesis . ​(Round to two decimal places as​ needed.) B. The data do not contain any outliers.

Answer 1